The time of rationalization has begun.

Consider Sen. Lamar Alexander (R-Tenn.), who is retiring and was therefore thought by many to be capable of mustering enough courage to stand up to President Trump by allowing witnesses to testify in the impeachment trial. Alexander appeared on “Meet the Press” on Sunday and expressed his view that while what the president did was wrong, it wasn’t bad enough to merit removal. Asked whether Trump will now feel emboldened to commit even more misdeeds, Alexander said this:

I don’t think so. I hope not. I mean, enduring an impeachment is something that nobody should like. Even the president said he didn’t want that on his resume. I don’t blame him. So, if a call like that gets you an impeachment, I would think he would think twice before he did it again.

Somehow managing to keep his jaw from dropping clear off his face, host Chuck Todd asked the obvious question: “What example in the life of Donald Trump has he been chastened?” In other words, has Trump ever gotten away with something (hiring undocumented workers? cheating on his taxes?) and then decided not to do it again?

To that, Alexander meekly said, “I haven’t studied his life that close.” Trump, did you say? Not that familiar with him.

This is what Republican “moderates” have come to. This is what someone like Alexander does with all the respect and admiration he spent decades accumulating. He slowly descends to the floor, gets on his hands and knees and makes himself a human footstool for the most immoral and corrupt president in American history. Alexander may not do it with the manic desperation of Sen. Lindsey O. Graham (R-S.C.) or the berserker rage of Rep. Jim Jordan (R-Ohio), but he does it all the same.

Of course, Alexander knows full well — as does every other American — that Trump, having been acquitted, will be more likely to cheat in this year’s election, not to mention commit all manner of other misconduct. As Axios’s Jonathan Swan reports, Trump and his advisers have a growing sense of “invincibility” that he can get away with nearly anything.

And it is not merely being acquitted that gives Trump this feeling, but the manner in which it happened. Not only will zero Republicans vote to convict him on the articles of impeachment, but all but two of them — including those who acknowledged that Trump’s coercion of Ukraine was inappropriate such as Sens. Rob Portman (Ohio), Lisa Murkowski (Alaska), and Marco Rubio (Fla.) — voted not to hear further evidence. Even the ones who pretended to take their constitutional responsibilities seriously were in the end active participants in what can only be called a coverup.

We haven’t really acknowledged how extraordinary that is. There are officials with direct knowledge of Trump’s actions and motivations, most notably former national security adviser John Bolton, and even the Republicans who say Trump did something wrong refuse to hear from them.

It isn’t hard to figure out why. They voted against hearing witnesses as much to protect themselves as to protect Trump. The more Trump’s naked corruption is given a full public hearing, the harder it becomes for someone with pretensions to integrity to defend him. Doing so is hard enough already; why make it harder on themselves?

So of course Trump feels invincible. How could he not, when senators such as Alexander, Portman, Murkowski and Rubio showed themselves to be such cowards?

Four years ago — when it was already obvious who Trump was — these Republicans had to explain why they would stand behind him. He’ll grow into the office, some said. He’ll have aides around him who will restrain him. It won’t be that bad.

But in the end, one rationalization stood above all others: Sure, Trump might be a con man and a walking amalgam of every character flaw a human being can possess, but at least he’s not Hillary Clinton. And that will be the Trump enablers’ safe harbor once again.

As soon as the Democrats have a nominee, the right-wing propaganda machine will spin up to turn that person into not merely a politician with whom Republicans have profound policy differences but the embodiment of evil — someone whose personal sins are beyond measure and whose goal is the literal destruction of America.

Then the enablers will breathe a sigh of relief. A few months from now, if anyone bothers asking them why they helped Trump cover up his offenses, they’ll say, “Look, that’s all in the past. What’s important now is that Joe Biden/Bernie Sanders/Elizabeth Warren/whoever not become president, because that would be the end of everything we hold dear.”

So it’s up to all of us not to forget what they did and why. Whatever else they might have done in their careers, this should be what defines them in history: They gave themselves to Donald Trump. What greater shame could there be?

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