No pol who has been for amnesty becomes reliable the other way.
Does he want to be Speaker for longer than 2 years?
McCarthy never has to face the wrath of the Texas GOP.
McCarthy will never ever go the way of Cantor. The open primary system means he wont lose.
Cantor and Brat would be on the ballot if it was in California.
Same with McMorris she will probably not lose and always make at least 2nd place.