They know they're the bad guys and they don't care.
They know what side they're on. They know they have chosen themselves over party and party over country. Power over everything. Worldly gains over God.
They cannot build, they can only destroy.
Everybody, literally everybody who is in the know, has given up on the idea that the Republican Party can behave.
The party is... gone. It's not a political party any more. There's no ideology, there's no actual policy. It will cling to power until it loses it, and then die.