What will Aerys do if he is not a mad man?

[joluoto2]

If Aerys wasn't mad alot of things before the Rgaegar/ Lyanna crisis would have gone differently. Tywin might for example still be a loyal Hand of the King, Duskendale might have been resolved differently and so on. With butterflies in place the Rhaegar/ Lyanna incident might not even happen.

[devilish]

Prior to the Targ rule, Westeros was dominated by constant wars between regions. These ancient feuds survived even after the Targs invasion. In matter of fact, Lord Paramounts used to prefer marrying their heirs either within family or with their bannermen's daughters rather to the daughters of other Lord Paramounts. For example Tywin was married to his cousin Joanna, Jon Arryn first wife was a Royce than he married his first cousin, Rickard was married to a Flint and Mace to a Hightower,

Prior to the rebellion this practice changed radically and suddenly. Cat Tully was promised to Brandan Stark, Lyanna was promised to Robert B, plans were made to have Lysa marrying to Jamie until she ended up marrying Jon Arryn and talks were also made to have Elia marrying within the Lannister family. While such phenomenon can't be used as solid proof of an imminent rebellion, one can't really exclude that the Lord Paramounts were exploring ways on how to become stronger and less reliant to the central government. Lets face it, without the Baratheon-Stark-Arryn Axis the Targs would still rule the land till this very day and things would have been much easier if only Jamie had married Lysa. 

Such details are significant because it captures the political scenario of the time. Stripped from their dragons and with families marrying one another, the Targs weren't as invincible as they were in the past. Talks of Tywin the true power in Westeros and of having Rhaegar replacing Aerys were made, which suggest that the crown wasn't passing from its best of moments. Aerys II didn't helped. He first pissed off Tywin Lannister and than he refused to hug his grand niece because she was too 'Dornish' for his taste. That's not the way a King treat his allies especially at a time when the other Lords are working 24/7 to become less reliant on central government. 

Many stress on Aerys decision of killing Brandon and Rickard as the reason why the rebellion started and they are right. However I wonder if decisions such as not punishing Rhaegar for what he did or keeping Brandon as ward wouldn't have translated in the same end result. After all the Starks rebelled even though Ned was still alive. Also what possibly could Aerys offer to the Northern alliance for it not to rebel? Rhaegar would have to handle Lyanna back to Rickard and possibly be punished for it. However what type of punishment could Aerys give to Rhaegar and what makes us think that Rhaegar would accept to be punished? For all we know Rhaegar could turn against his father and considering that he had Lyanna Stark in his hands and that Aerys wasn't particularly loved, he might have to face a silly situation were  Rhaegar would have been able to raise enough troops to depose his father. In matter of fact if Rhaegar was able to convince Tywin and Doran to act, than his armies could easily reach KL before anybody could act and kick Aerys out of the Iron throne.  

 

So seriously, Aerys had laid his bed long before Lyanna's kidnap. Mind you, Aerys could still save the day at that point. However with the Lannisters, Baratheons and Starks pissed off, the Martells linked to Rhaegar, the Starks linked to the Tullys and the Arryns emotionally linked to the Baratheons and Starks, the Targs were in a dangerous situation. If I was Aerys I would 

a- arrest Brandon but I would treat him as a ward rather than a prisoner

b- summon Rickard but talk to him like a fellow father who lost control over their unreasonable children rather than a King whose talking to a subject whose son had rebelled against the crown

c- send letters to the 7 kingdoms to try to sort things up. Concessions should be given if possible

- Appoint Lord Arryn as an independent mediator between the Starks/Baratheons and the crown
- Ask Tywin to return as hand of the King. In return I would release Jamie from KG duty and offer Rhaenys to him in marriage
- Ensure Doran than whatever happens Aegon would still remain heir to the crown and that Rhaegar will be punished for his transgressions
- Give the same assurances to the Starks and the Baratheons
- Summon Rhaegar back to KL. 
-  Propose a future marriage between Aegon and Margaery Tyrell

If Rhaegar returns peacefully, than I will have him arrested and than I would summon all Lord Paramounts to come to KL and act as jury to Rhaegar's trial.

If Lyanna truly love Rhaegar and she fled with Rhaegar out of her own will

- Rhaegar would be stripped from his inheritance and the crown prince title will move to his son Aegon
- Rhaegar would be exiled to Dragonstone were he can live with Lyanna for the rest of their lives. All children will be legitimised HOWEVER they will have no claim to the iron throne. The male children of that marriage will be trained to become knights (hopefully in the KG) while the daughters will be married to Lords as befitting to children with Stark-Targ blood in them
- Robert B will be given more lands and he will be appointed as a member of the small council (Master of war)

If Lyanna was kidnapped and raped by Rhaegar

- Rhaegar will be sent to the wall. The crown prince title will move to his son Aegon
- Lyanna will be given the chance to marry Robert B (if he still wants her), stay single (and be maintained for the rest of her life by the crown) or return to her father
- Her son will be legitimized as a Targ and be trained as a Knight
- Robert B will be given more lands and he will be appointed as a member of the small council (Master of war)

If Rhaegar refuse to return peacefully

-Declare him as a traitor and call the banners against him. 
-If captured alive put him on trial. If he kidnapped and raped Lyanna have him killed. If they escaped out of love than have Robert B, Arryn, Stark, Martell and Tywin decide his fate
- Appoint his son Aegon as heir
- Robert B will be given more lands and he will be appointed as a member of the small council (Master of war)

 

 

[joluoto2]

To elaborate on butterflies involved. If Aerys wasn't mad there is a big probability the tourney at Harrenhal might not have happened (since it seems it was bankrolled by Rhaegar, and the original intent was for it to work as an informal Great Council discussing Aerys' madness, however all such plans were foiled by Aerys actually attending the tourney). And that means Rhaegar never meet Lyanna in the first place.

[Qhorin Halfhand and Yoren]

Arrest Brandon. Call his father and Rhaegar in the capital and try to sort out what happened. Do not let either Rhaegar or the Starks leave until the issue is resolved peacefully and call for Robert and Doran to go to the capital or send representatives. Genuinely try for a compromise to be made.

 

If he got a Machiavellian tywinisque point of view, strike one against the alliance should be something more decisive than simply killing nobles in the way he did. Perhaps again an invasion of the riverlands, while not killing the Starks and their noble companions but holding them hostage, transforming their status from guests of the red keep to hostages and prisoners.

Obviously you need to also spread propaganda throughout the kingdom, maybe lie about Hoster Tully conspiring and saying that he wishes to kill you and usurp the kingdom. 

Also, prior to the war, call back Tywin as hand and promise that you will reward him if he serves you faithfully and call of him to join and help start the war. (Give him anything required that you as Aerys can give).  Of course, you know that Tywin is too prideful and scheming and the Lannisters too vainglorious and see themseves as the next targaryens so you plan to backstab him in the end. Hopefully through a way that can't be proven back to you. Maybe poison and you pointing the finger at one of the inevitable noble victims of Tywin in the war. 

 

 

[TimJames]

Misplaced Post.

[SeanF]

If Aerys wasn't mad alot of things before the Rgaegar/ Lyanna crisis would have gone differently. Tywin might for example still be a loyal Hand of the King, Duskendale might have been resolved differently and so on. With butterflies in place the Rhaegar/ Lyanna incident might not even happen.

"I wouldn't start from here" as the saying goes.

Assuming that I'm Aerys, and a reasonably competent ruler, I'd have made a point of keeping Tywin close, and betrothing Rhaegar to Cersei.  If Rhaegar subsequently eloped with Lyanna, I'd have very clearly ruled that his children by Cersei were part of the line of succession, and that any children by Lyanna (whether or not a bigamous marriage had taken place) would not be deemed legitimate.  That way, I keep Tywin on board.  At that point, I would have given serious thought to disinheriting Rhaegar completely, in favour of Aegon.  In fact, a disinherited Rhaegar, now married to Lyanna, would have the advantage of disrupting the very threatening alliance that was building up between the Baratheon, Tully, Arryn, and Stark families.

I'd have been looking to betroth Viserys to a Tyrell, to keep that family on board.

[WSmith84]

The thing is, Aerys not being mad probably would have changed everything. But I'll assume, for the sake of the question, that Rhaegar and Lyanna ran off for love/lust. I'll also assume that everything prior to this point happened exactly the same, but that now the madness has passed and I'm aware of what a mess I have made.

Well, I (Aerys) would now have three LP Houses that would be majorly pissed; Martell, Baratheon and Stark. I'd arrest Brandon and his companions (assuming Brandon behaves the same) and put them in some nice, comfortable tower cells. I'd go to Brandon and reassure him that justice will be served, and write to Lord Rickard the same thing. Then, I'd send my KG to retrieve Rhaegar and Lyanna.

When they arrived in the capital (assuming Rhaegar didn't resist) my next action would depend on whether or not Lyanna had been 'dishonoured' or not. If not, well and good. I'd return Lyanna to her father, which should keep the Baratheon-Stark marriage intact and the Martells shouldn't have anything to worry about. I'd release Brandon and his companions as well, though I would insist that Benjen and Ned Stark come to court and remain as 'guests' and would insist that the Lords of the men who rode with Brandon send a 'guest' to court as well. I'd also ask Jon Arryn to serve as Hand. This should make him less likely to rebel, just in case Rickard's power bloc actually means something. Rhaegar would be sent to the Wall. His decision to run off with Lyanna was immensely foolish (again, assuming love/lust here) and he shouldn't be sitting the Throne. I'd declare Aegon as heir and arrange a betrothal between Viserys and Arianne, and would invite either Doran or Oberyn to sit on the Small Council and have a hand in young Aegon's education. Upon hearing of Mace Tyrell having a daughter, I'd offer a marriage between her and Aegon, bringing Highgarden to my side.

If Lyanna was dishonoured, well, things become a bit trickier. Rhaegar still goes to the Wall and Aegon is still named heir. If she is with child, I will insist that Rhaegar acknowledge the baby as a bastard (and I'll make whatever threats I need to). I'll have the baby fostered in Dorne, with the Martells. That should ensure that the baby doesn't grow up with ideas of replacing his half-brother. I'd insist that Ned and Benjen came to court as 'guests' as punishment for Brandon's actions and would insist that the Lords of the men who rode with Brandon send a 'guest' to court as well. I'd allow Lord Rickard to decide what to do with Lyanna and release Brandon. I'd offer Rickard the position of Hand of the King as recompense for the loss of the Stark-Baratheon alliance and promise to help find good matches for his other sons. I'd again offer a Small Council position to Doran or Oberyn and betrothe Viserys to Arianne. I'd write to Tywin, offering to arrange a match between Robert and Cersei. Hopefully, a hot young bride from a rich family should please Robert and combined with Rhaegar being sent to the Wall it should appease him. No doubt as the years rolled by, Robert would grow to hate me for inflicting Cersei on him, but I'd have no way of predicting that train-wreck of a marriage. Again, upon hearing of Mace Tyrell's daughter being born, I'd offer a marriage between Aegon and her, to bring Highgarden to my side. Assuming all is well and the years roll on peacefully, I'd remind Rickard of the Pact of Ice and Fire (assuming that he'd served well and faithfully) and how it was never fulfilled, and offer to finally fulfill it (if that is possible).

Actually, assuming the first part of my post, I'd probably have a bath, cut my nails and trim my hair first. Then do all the rest.

[devilish]

Am I the only one to think that the Targ reign was close to the end irrespective on whether Aerys existed or not? I agree that Aerys had accelerated things up however there's enough evidence to suggest that the Lord Paramounts were preparing for a big change. In fact prior to the war we see a record number of Lord Paramount daughters and sons marrying one another and therefore sealing alliances in the eventuality of an imminent war. Such phenomenon was unprecedented prior and during the Targ's rule and was only repeated during the war of 5 kings (Renly-Margaery, Joffrey/Tommen-Margaery, Tyrion-Sansa)

Its only fair to suggest that a breakthrough was somehow imminent. The Targs were considered by foreigners who ruled by right of conquest. They were pretty elitist (ie preferring to intermarry rather than mix with the 'commoners'). With the dragons gone and the common people pretty attached to their Lord Paramounts rather than their Targ kings, why should the Lord Paramounts keep on obeying them? Its not as if the Targs could force them to do that at that point 

[devilish]

The thing is, Aerys not being mad probably would have changed everything. But I'll assume, for the sake of the question, that Rhaegar and Lyanna ran off for love/lust. I'll also assume that everything prior to this point happened exactly the same, but that now the madness has passed and I'm aware of what a mess I have made.

Well, I (Aerys) would now have three LP Houses that would be majorly pissed; Martell, Baratheon and Stark. I'd arrest Brandon and his companions (assuming Brandon behaves the same) and put them in some nice, comfortable tower cells. I'd go to Brandon and reassure him that justice will be served, and write to Lord Rickard the same thing. Then, I'd send my KG to retrieve Rhaegar and Lyanna.

When they arrived in the capital (assuming Rhaegar didn't resist) my next action would depend on whether or not Lyanna had been 'dishonoured' or not. If not, well and good. I'd return Lyanna to her father, which should keep the Baratheon-Stark marriage intact and the Martells shouldn't have anything to worry about. I'd release Brandon and his companions as well, though I would insist that Benjen and Ned Stark come to court and remain as 'guests' and would insist that the Lords of the men who rode with Brandon send a 'guest' to court as well. I'd also ask Jon Arryn to serve as Hand. This should make him less likely to rebel, just in case Rickard's power bloc actually means something. Rhaegar would be sent to the Wall. His decision to run off with Lyanna was immensely foolish (again, assuming love/lust here) and he shouldn't be sitting the Throne. I'd declare Aegon as heir and arrange a betrothal between Viserys and Arianne, and would invite either Doran or Oberyn to sit on the Small Council and have a hand in young Aegon's education. Upon hearing of Mace Tyrell having a daughter, I'd offer a marriage between her and Aegon, bringing Highgarden to my side.

If Lyanna was dishonoured, well, things become a bit trickier. Rhaegar still goes to the Wall and Aegon is still named heir. If she is with child, I will insist that Rhaegar acknowledge the baby as a bastard (and I'll make whatever threats I need to). I'll have the baby fostered in Dorne, with the Martells. That should ensure that the baby doesn't grow up with ideas of replacing his half-brother. I'd insist that Ned and Benjen came to court as 'guests' as punishment for Brandon's actions and would insist that the Lords of the men who rode with Brandon send a 'guest' to court as well. I'd allow Lord Rickard to decide what to do with Lyanna and release Brandon. I'd offer Rickard the position of Hand of the King as recompense for the loss of the Stark-Baratheon alliance and promise to help find good matches for his other sons. I'd again offer a Small Council position to Doran or Oberyn and betrothe Viserys to Arianne. I'd write to Tywin, offering to arrange a match between Robert and Cersei. Hopefully, a hot young bride from a rich family should please Robert and combined with Rhaegar being sent to the Wall it should appease him. No doubt as the years rolled by, Robert would grow to hate me for inflicting Cersei on him, but I'd have no way of predicting that train-wreck of a marriage. Again, upon hearing of Mace Tyrell's daughter being born, I'd offer a marriage between Aegon and her, to bring Highgarden to my side. Assuming all is well and the years roll on peacefully, I'd remind Rickard of the Pact of Ice and Fire (assuming that he'd served well and faithfully) and how it was never fulfilled, and offer to finally fulfill it (if that is possible).

Actually, assuming the first part of my post, I'd probably have a bath, cut my nails and trim my hair first. Then do all the rest.

That's the problem. Why would Rickard obey at that point? The Arryn-Baratheon-Starks-Tully alliance was all but sealed. Aerys pissed off the Lannisters and his son pissed off the Martells. Considering the xenophobia in Westeros and Aerys inability to negotiate with his Lord Paramounts than a couple of good moves from Rickard could see him stronger than the King. 

In many ways Aerys was lucky. Tywin's reluctance in committing himself to the rebel's cause + the surprising commitment from the Tyrells gave the royalists a fighting chance. If Tywin joined the rebellion from day 1 than the rebellion would have been short and relatively painless  

[WSmith84]

That's the problem. Why would Rickard obey at that point? The Arryn-Baratheon-Starks-Tully alliance was all but sealed. Aerys pissed off the Lannisters and his son pissed off the Martells. Considering the xenophobia in Westeros and Aerys inability to negotiate with his Lord Paramounts than a couple of good moves from Rickard could see him stronger than the King. 

In many ways Aerys was lucky. Tywin's reluctance in committing himself to the rebel's cause + the surprising commitment from the Tyrells gave the royalists a fighting chance. If Tywin joined the rebellion from day 1 than the rebellion would have been short and relatively painless  

Well, he does hold (in this scenario) both Lyanna and Brandon hostage, and once Rickard is in KL, he is a hostage himself, as would be Ned and Benjen. Of course, Rickard may well end up stronger than the King in this scenario, but as long as he is supportive of the Targaryen regime, does it really matter? But I did suggest bringing the Tyrells to the table, to counterbalance this. And the Baratheon-Stark alliance would be ruined if Lyanna was 'dishonoured'. And without Aerys committing the attrocities he did (Brandon and Rickard's deaths, the demand for the deaths of Ned and Robert) many lords might be more reluctant to rebel against him.

[devilish]

Well, he does hold (in this scenario) both Lyanna and Brandon hostage, and once Rickard is in KL, he is a hostage himself, as would be Ned and Benjen. Of course, Rickard may well end up stronger than the King in this scenario, but as long as he is supportive of the Targaryen regime, does it really matter? But I did suggest bringing the Tyrells to the table, to counterbalance this. And the Baratheon-Stark alliance would be ruined if Lyanna was 'dishonoured'. And without Aerys committing the attrocities he did (Brandon and Rickard's deaths, the demand for the deaths of Ned and Robert) many lords might be more reluctant to rebel against him.

Sansa and Ned were Lannister hostages, yet that didn't stop Robb to call the banners. Jamie was a Stark's hostage (and Aerys KG) but that hasn't forced Tywin to turn tail to the Westerlands or to join the royalists. Theon Greyjoy was Ned's ward but that didn't stop Balon to return to reaving the day the 7 kingdoms entered into civil war. Also Oberyn Martell was a potential hostage when he was at KL and Mycella was a potential hostage at Dorne. That had no bearing to politics whatsoever. 

Politics are more complicated than this and rely heavily on reputation, especially in a scenario where the King has to rely on the good will of the Lord Paramounts for protection, financing and even food. If a King start cutting heads of the big families members than it would only be a matter of time before these families would start contemplating whether its wise to support that King after all. Think about it. Aerys had never lift one finger against the Tullys and the Arryns and yet they still fought against him. The Tyrells passed most of the time sieging Storm's end and that despite the fact that it had no military significance to the war whatsoever. Joffrey was killed by a Tyrell and that despite the fact that he never lifted a finger against a Tyrell before, while Robert B accepted Balon's surrender instead of righfully crushing it under his warhammer. Its never a good idea to built a bad reputation and to make long term enemies especially among subjects you depend so heavily upon

[SeanF]

That's the problem. Why would Rickard obey at that point? The Arryn-Baratheon-Starks-Tully alliance was all but sealed. Aerys pissed off the Lannisters and his son pissed off the Martells. Considering the xenophobia in Westeros and Aerys inability to negotiate with his Lord Paramounts than a couple of good moves from Rickard could see him stronger than the King. 

In many ways Aerys was lucky. Tywin's reluctance in committing himself to the rebel's cause + the surprising commitment from the Tyrells gave the royalists a fighting chance. If Tywin joined the rebellion from day 1 than the rebellion would have been short and relatively painless  

If Ser Kevan's recollection is correct, then Tywin would have accepted being restored as Hand, and the outcome at the Trident might have been very different.

[devilish]

If Ser Kevan's recollection is correct, then Tywin would have accepted being restored as Hand, and the outcome at the Trident might have been very different.

God knows what Tywin would have done afterwards. Maybe he would have made sure that both armies (royalists and rebels) annihilated one another while keeping his troops protected. In that way he would have found no resistance when he decided to move to KL and kill the old man, only to take his place. Lannisters paying their debts and all

[SeanF]

God knows what Tywin would have done afterwards. Maybe he would have made sure that both armies (royalists and rebels) annihilated one another while keeping his troops protected. In that way he would have found no resistance when he decided to move to KL and kill the old man, only to take his place. Lannisters paying their debts and all

I think he'd have preferred to install Rhaegar as King, or if Rhaegar had been killed, Aegon.  I'm sure he'd have removed Aerys.

[devilish]

I think he'd have preferred to install Rhaegar as King, or if Rhaegar had been killed, Aegon.  I'm sure he'd have removed Aerys.

Rhaegar lost his utility the day he married Elia Martell. Hence why Tywin showed no remorse in butchering his two children. At that point I think he would have supported Viserys rise to the throne ie a young man who could easily be manipulated and married to

[Artos Cold]

Honestly, i think Rickard would have been fine with Rhaegar remaining heir, if Lyanna had gone willingly and Rhaegar agreed to take her as his wife. 

Brandon gets a slap on the wrist and Robert gets a formal apology and maybe some gold as recompense. A year later Jaehaerys Targaryen id born and everybody lives happily ever after. 

[WSmith84]

Honestly, i think Rickard would have been fine with Rhaegar remaining heir, if Lyanna had gone willingly and Rhaegar agreed to take her as his wife. 

Brandon gets a slap on the wrist and Robert gets a formal apology and maybe some gold as recompense. A year later Jaehaerys Targaryen id born and everybody lives happily ever after. 

But in that scenario little Jaehaerys Targaryen inherits nothing and the Starks lose the Stormlands. And Dorne would never rest easy with a second son of Rhaegar from a more powerful House (with some powerful connections) around. What if Rickard decides that he wants his blood on the throne? What if Jaehaerys grows up and feels that he would make a better King than Aegon? What if those at court who hate the Dornish want to use Jaehaerys to start a conflict? What if an accident happens to one of the princes? Marrying Lyanna is just asking for trouble. It's asking for a second Dance. And no way does Robert just accept an apology and gold. He'd want more than that.

[redtree]

If Ser Kevan's recollection is correct, then Tywin would have accepted being restored as Hand, and the outcome at the Trident might have been very different.

If Tywin were hand he'd have burned Stoney Sept to the ground, cruel ? Maybe, but those people protected one of the head of the rebels so his action would be justified. Aerys would still be on the thrones and who knows what would happen to Lyanna, we know Tywin wanted so badly for his future grandson to sit on the IT. I see some "mishaps" would happen to baby Aegon and Jon

[WSmith84]

Sansa and Ned were Lannister hostages, yet that didn't stop Robb to call the banners. Jamie was a Stark's hostage (and Aerys KG) but that hasn't forced Tywin to turn tail to the Westerlands or to join the royalists. Theon Greyjoy was Ned's ward but that didn't stop Balon to return to reaving the day the 7 kingdoms entered into civil war. Also Oberyn Martell was a potential hostage when he was at KL and Mycella was a potential hostage at Dorne. That had no bearing to politics whatsoever. 

In that situation, Ned was almost certainly going to be beheaded and there was no indication that Sansa and Arya would be released. And Robb was asked to come to KL, and all agreed that if he went he wouldn't be allowed to leave. In this situation, Aerys would be reassuring Rickard that his children would be returned to him unharmed. Once Lyanna returns to KL and it's discovered that she's been dishonoured, Aerys would then offer Rickard the position as Hand and offer to help find marriages for his other sons (perhaps Ashara Dayne). In case 1, Robb is being told that his father is a traitor and will die and that his sisters will remain hostages. In case 2, Rickard is being told that despite Brandon's clear treason, Brandon will be released and Lyanna will be returned safely and Rickard is being offered an extremely powerful political position. Those cases are very different.

Politics are more complicated than this and rely heavily on reputation, especially in a scenario where the King has to rely on the good will of the Lord Paramounts for protection, financing and even food. If a King start cutting heads of the big families members than it would only be a matter of time before these families would start contemplating whether its wise to support that King after all. Think about it. Aerys had never lift one finger against the Tullys and the Arryns and yet they still fought against him.

Yes, Aerys never lifted a finger against the Tullys or Arryns. Except for, you know, killing Jon Arryn's nephew and killing the man Catelyn Tully was going to marry, as well as a bunch of lordlings sworn to the Tullys. And my proposal contained nothing about killing any lords; Rhaegar would be sent to the Wall, but that was as far as it went. 

The Tyrells passed most of the time sieging Storm's end and that despite the fact that it had no military significance to the war whatsoever.

Sorry, but George disagrees. There's an SSM where he talks about the importance of Storm's End. Besides, whoever was head of the Royal forces at the time could have asked for more troops and commanders from the Tyrell host.

Joffrey was killed by a Tyrell and that despite the fact that he never lifted a finger against a Tyrell before, while Robert B accepted Balon's surrender instead of righfully crushing it under his warhammer. Its never a good idea to built a bad reputation and to make long term enemies especially among subjects you depend so heavily upon

Again, my proposal had nothing to do with killing any lords. It was all about appeasing those who were annoyed and forging new alliances with other powerful Houses.

[devilish]

Part 1

Ned's death took everyone by surprise include the Lannisters. It was a much more sensible strategy to keep Ned alive as hostage with the promise of him ending up as a member of the night's watch if Robb behaved. The situation is pretty similar in both cases. A Stark challenged the crown and the King summoned their representative at Winterfell to answer for such crimes.  Killing a Lord Paramount or his offspring is rarely a great idea as that would lead to

a- his children and grandchildren will remember and most of them lead armies

b- other Lord Paramounts will be apalled by such decision and others will start wondering if they will be next. Hence why an issue between Baratheon, Starks and Targs ended up in a full blown rebellion

Hence why hostages, while being an asset, should be handled with care. In Aerys case, his outlandish action caused the Baratheons, Starks, Tullys and Arryns to rebel. In Joffrey's case he should thank Lysa's craven nature and Renly + Robb's over ambition because he could have easily ended up with Baratheons, Arryns, Tyrells, Starks and Tullys marching all of KL. Not to forget that at that point the Martells would have probably joined the party too, (paying their debts and all.

As said before reputation is key here. Rickard genuinely believed in the Targ's good will in sorting things up in an honourable way. Robb did not and called the banners.

Part 2-3

You have to understand what a rebellion really means. Thousands of soldiers will be deployed with no guarantee that their bannermen will answer their call or simply turn against them. A defeat may cost the family their entire dynasty. Such risk kept the great and ruthless Tywin Lannister in line for years as Aerys humiliated and provoked him time and time again. Would a lord paramount risk that for a nephew or a future son in law? I much doubt it. 

I believe that the Targeryan era was heading towards its slow decline with the Lord Paramounts busy sealing alliances with one another through marriages. I doubt that at that point anyone wanted to make a move just yet as they hoped that Rhaegar would one day succeed and be a better king than his mad father. Hence why I believe that what Rhaegar did was serious (not a deal breaker but serious). Hence why I believe that the last thing Aerys should have done was to threaten the disgrunted families with his hostages or demand sons as 'guests'. That could have easily degenerated into a revolt. 

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The situation is pretty easy to understand. Unlike Rickard who had Tully and Baratheon support + Arryn's friendship, Aerys had little support. Throughout his life he mistreated the Lannisters and he insulted the Martells (refusing to hug Rhaenys because she look too Dornish) and therefore there were nothing to suggest that these two houses would back him up in times of need. To make matters worse there were rumours going on that Rhaegar was planning to dispose of the King. Under such circumstances Aerys simply couldn't afford a war. 

The only way to come out of this mess was to talk to Rickard not as a king to his subject but as two fathers who lost control over their respective sons, promising that Rhaegar will be punished for his actions and that Brandon will be pardoned and released after this mess was over if Rickard promises to help him sort this mess. Once the Baratheon-Stark-Arryn-Tully had been sorted, Id send letters to Dorran promising that nothing would harm Elia or her children and I would try to patch things up with Tywin, ensuring him the release of Jamie from KG and the marriage between future heir Viserys and Cersei as sweetener if he commits his army to the cause. Finally Id suggest the marriage between Rhaenys (3rd heir to the throne) and Willas Tyrell to make sure that the Tyrells will be fully committed to the cause and between Aegon Targaryen (2nd heir to the throne) and Arianne Martell to try to make sure that the Dorne wont rebel