Sens. Rob Portman, R-Ohio, and Cory Gardner, R-Colo., have learned nothing over the past two years, politically speaking. And from a moral and intellectual standpoint, they seem to have regressed.

Both are already endorsing President Donald Trump — because Trump’s the incumbent, you see. Consider the logic here, as reported by the conservative website Independent Journal Review:

“Portman now says he plans to back the president in 2020.

” ‘I intended to support the Republican incumbent,’ he told IJR. And like other Republicans, Portman said he’s basically supporting Trump because he’s already the president.

” ‘What changed?’ Portman replied when asked why he’s changed his mind. ‘Well, he’s the incumbent. I mean, he’s in office, I work with him every day.

” ‘I disagree with him publicly and privately when appropriate. But I also get a lot done, and I get that done with him. So we work with the White House, and I think that’s important for Ohio,’ Portman added.”

Portman apparently doesn’t care about the obvious indications of the president’s abject unfitness, his bizarre fondness for Russian President Vladimir Putin, and Trump’s refusal to accept reality even in the face of the unanimous judgment of the intelligence community and the considerable evidence that he obstructed justice and lied to the American people about ties to Russia. Hey, he’s there in the Oval Office, so he’s my guy!

Gardner is just as bad:

“Sen. Cory Gardner (R-Colo.), another Republican senator who vocally opposed Trump in 2016, told IJR that he’s endorsing the president now because it’s the ‘right thing to do for Colorado.’

” ‘Look, there are things here — look, I’ve made it very clear that where I agree with the president, we will agree or where I disagree, we will disagree,’ Gardner told IJR. ‘But I’m going to fight like hell for Colorado, and we’ve done some good things for Colorado.

” ‘I know what Kamala Harris and I know what Bernie Sanders will do to Colorado, and that’s why I’ll be supporting the president,’ Gardner added.”

It doesn’t seem to occur to him that someone more to his political liking might be the Democratic nominee or that a fine Republican challenger could emerge. It’s fair to say Gardner is in extreme political peril given the increasingly Democratic bent of the state; this sure won’t help.

And when you are looking for examples of political spinelessness, Sen. Marco Rubio, R-Fla., never disappoints. (” ‘Why, is someone running against him?’ Sen. Marco Rubio (R-Fla.) replied when asked if he plans to back Trump, his former 2016 rival. ‘It’s my intention, of course, to support the nominee. And he’ll be the nominee.'”) No one ever accused him of having an abundance of political imagination or independence.

These Republicans have internalized no lessons, it seems, from the morally and intellectually ruinous effort to defend Trump at all costs. They cannot imagine a political universe in which he is not the nominee — or they are afraid to say so. They, in short, remain enablers of Trump’s incompetent, deceitful and cruel administration. They bear blame for his attacks on democratic institutions, his normalization of bigotry, and his undermining of U.S. influence and stature in the world.

When it comes to national security, other Republicans have recognized that Trump has become a menace. The incident in which the spy chiefs told the country what the world really looks like provoked another Trump tweet tantrum.

“I prefer the President would stay off Twitter, particularly with regard to these important national security issues where you’ve got people who are experts and have the background and are professionals,” said Sen John Thune, R-S.D., according to a CNN report. “I think in those cases when it comes to their judgment, take into consideration what they’re saying. … I think we need to trust their judgment.”

And yet the vast majority of elected Republicans are willing to leave a wholly irrational commander in chief in place — and vote for another four years of his rants, self-delusion and out-and-out lies.

What is remarkable is that even when the possibility exists that Trump put his own private interests (either financial or personal) over the defense of the United States when it comes to foreign powers (Russia or Saudi Arabia, to name two), they cannot envision abandoning him. They would rather have someone who very possibly betrayed his country than — oh, the horror! — a Democrat. They aren’t even willing to pursue the idea of a sane, ethical and fit Republican challenger.

I’m often asked why Republicans behave in such a sniveling fashion, putting Trump’s survival above country. These politicians are by and large careerists, trying to figure out how to go along to get along; they live in fear of a primary challenge — or an angry presidential tweet or critical Sean Hannity segment. They cling to Trump like a life raft, despite replete evidence he’s an anvil. Undaunted by the 2018 results, they would rather try to meld in with the herd of Republicans than risk being gobbled up by Trumpists.

The GOP is not only in need of a presidential primary challenger; it’s also in need of Republican primary challengers in Senate and House races. The party and the country need an entire new crop of senators and other elected officials who understand their obligation is to the Constitution and the country, not to a patently unfit and reckless president.

Presidents come and go — and when this one goes, we should hope his enablers go as well. They’ve been tested by the times and failed.

Jennifer Rubin writes reported opinion for The Washington Post.

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