Thats not really the same thing imo, House Bolton is just that, a single house not a coalition like the north.
Breaking a stick in a broom is easier to than breaking the whole broom.
Anyway, what kinda message does it send, allowing a house rebelling several times without major consequences? Killing the current head of the rebelling house wasn't enough apparently,in the long run.(assuming thats what happened)
Ok. Let me explain.
A King grants the Lord Paramounts their Lands and titles. In exchange for those, the Lord Paramounts swear fealty, which is essentially a guarantee that they will pay taxes to the crowns of a certain percentage, and perform military service when the King commands it.
A Lord Paramount has the same relationship to the Lordlings below him. He grants them their lands and titles (in the name of the King) and they swear fealty, providing taxes and military service when needed (to both Liege Lord and King).
Lesser Lordlings have the same relationship with Petty Lords and Knights. They grant then lands and titles (in the name of the Liege Lord and King) and they swear fealty, providing taxes and military service (to Lordling, Liege Lord, and King)
Every link in the feudal chain is sworn to someone above them except the King, and you could argue that since his power was thought to have derived from the gods, that he is too.
If the Starks extinguish one of the Lordlings houses, they risk not only rebellion in their lands because they've broken that feudal contract, but also risk that the Crown could take action against them because that house also owes fealty to the throne as well as the Starks. It's no matter what level of the feudal chain they're on. It's the same dynamic all the way to the top, hence the Aerys reference.
By allowing them to continue to exist, the Starks honored the feudal contract, and played it safe with their own sworn Lords, and the King they were sworn to as well.
As to what sort of message it sends- it sends the message that you're fair and just, and follow the oaths you've sworn.
Even Tywin Lannister who famously extinguished the Houses of Reyne and Tarbek did not believe that was the norm.
When your enemies defy you, you must serve them steel and fire. When they go to their knees, however, you must help them back to their feet. Elsewise no man will ever bend the knee to you.
Edited by Bog Devil of Greywater, 15 July 2014 - 07:05 PM.