National Review Editor on Conservatism: Trump Shook It and It Fell Down "Conservatism had not updated itself to deal with the new realities."

 -- A key conservative Republican thinks that Donald Trump, win or lose, has exposed a serious problem with Republicanism.

Speaking to ABC News' Jonathan Karl and Rick Klein on the "Powerhouse Politics" podcast, Lowry described his take on conservatives.

"The right had become too beholden to these old cliched policies and rhetorical tropes associated with Ronald Reagan," said Rich Lowry, the editor of National Review. "Everyone thought that there was this kind of sturdy house of Reagan and everybody had to occupy a room within it and ... genuflect at the door."

"Donald Trump didn't do that," he continued. "He basically shook the structure, and the whole thing sort of fell down, which goes to the fact that conservatism had not updated itself to deal with the new realities on the ground."

Lowry addressed the many Republican lawmakers who have flip-flopped on supporting Trump.

"I think a lot of these folks have gotten in trouble and kind of disgraced themselves because they haven't staked out one position and have just stuck with it," Lowry said. "I don't pour contempt on anyone who realizes all of Trump's failings and just says, 'This is a 51-49 question, and I am with Trump.' I respect that entirely. But it's a little hard to respect the people who didn't endorse, then endorsed, then unendorsed, then re-endorsed. If that is where your state of mind is, just ... don't say anything. Just shut up."

Lowry also said Rep. Paul Ryan's speakership is definitely in trouble.

"He has a major target on his back. I don't know if they will get him this time, but his life will be like [John] Boehner's, going forward. There will be a constant threat."

Lowry was asked which Republicans are best positioned for a White House run in 2020.

He said one is "Ted Cruz, who literally, every hour of the day, is plotting how he actually grasps the brass ring next time around." Others are Sen. Tom Cotton and Sen. Ben Sasse, who "represent opposite poles of how you deal with Donald Trump," Lowry added.

So how about Ohio Gov. John Kasich?

"I think Kasich would be in the same spot he was this time around and someone who in theory would have a lot of appeal in a general election but actually has to win Republican votes to get there. And he demonstrated no capacity to get there in 2016, and I don't see how it would be any different in 2020," Lowry said. "But the fact is if he were running, he would probably be winning by 10 points."

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