John Cornyn — a four term Texas senator built in what many called an establishment Republican lab — just lost his primary runoff to Texas Attorney General Ken Paxton by 27 crushing points, one week after President Trump gave Paxton his endorsement and called him a true MAGA warrior.

The same week Trump wiped out two incumbent lawmakers in their primaries, Senate Republicans discovered something that had eluded them for 16 months — the word no — with even Ted Cruz publicly condemning Trump’s $1.8 billion anti-weaponization fund as Republican senators packed up and went home in open defiance. Trump just proved he can take out anyone who crosses him — and the Senate just proved they have a limit. Nobody knows yet which one of them blinks first.