I don’t think its anymore clearer for Arnold, he took up arms against the very men he commanded and fought side by side with, what every value of principal he held so dearly was easily (and cheaply) bought for his treachery.I’m not sure if it’s as black and white as to say Arnold made war on his own kind. He was born a British citizen in a British colony. As for Washington he took the oath to the King in the militia, probably more than once, but disregarded that oath later when it suited him. Yet he’s not remembered as an oath-breaking traitor, probably because he won.
All you have to do is look at his post war actions, his lobbying to have his expenses covered were even denied by the Crown who said he had no ability to substantiate the claims, the very same treatment that was given to him by Congress and the Continentals. Arnold had always claimed to have been mistreated by Congress and the Army, well they certainly had reasonable cause to do so, in short he was scheming liar and both the Americans and British knew it.
He was really led by his mercenary nature, what ever true values of patriotism and liberty he held on to were lost sometime after 1776 after Quebec.
In the end Arnold was neither British or American, a man without a home or an identity. Even his trophy wife was contemptuous of him.
Had Washington not placed Arnold in command of Philadelphia, things would have been far different, Arnold may have assumed command of the Southern Army after Gate’s failure At Camden, that’s how close he was really to becoming a true hero.