Every week — nearly every day — brings fresh, stomach-churning evidence of President Trump’s unfitness for office. The latest may be the most revolting.

Confronted with incontrovertible proof that his son leapt at the prospect of meeting with a “Russian government attorney” offering to dish dirt on Hillary Clinton as “part of Russia and its government’s support” for his candidacy, the president took the position that this was political business as usual.

His first public reaction, in an interview with Reuters, was that “many people would have held that meeting.” The next day, Trump ratcheted up that astonishing assertion, from “many” to “most,” asserting, “I think from a practical standpoint, most people would have taken that meeting. . . . Politics isn’t the nicest business in the world, but it’s very standard.”

No. It. Isn’t.

Donald Trump Jr. at least had the decency to admit, in his interview with Fox News’s Sean Hannity, that, “in retrospect, I probably would’ve done things a little differently.” Not his father. I know being Trump means never having to say you’re sorry. I understand the fierce parental instinct to defend your erring child, even if that child is a 39-year-old father of five.

(Adriana Usero,Kate Woodsome/The Washington Post)

But this meeting was unacceptable. It was not even in the exurbs of appropriate. Hard to believe this really requires spelling out, but apparently it does, so here goes: A candidate for president of the United States and his campaign have no business, none, trucking with an emissary of a foreign government peddling incriminating information about their opponent.

That this meeting was explicitly described as an element of a Russian plot to influence the U.S. election is icing on an already repulsive cake. That the target of this feeler — the candidate’s son — embraced such meddling rather than recoiling from it only adds to the sordidness of the episode.

And that the intended beneficiary, now the sitting president of the United States, is unable and unwilling to accept that fact should be chilling to every patriotic American. Perhaps he is incapable of ever acknowledging wrongdoing. That only adds to the chill.

As does Trump’s staggering refusal to recognize the reality of Russian attempts to interfere in the election. What was Trump doing, at this late stage, asking Russian President Vladimir Putin if he meddled?

“I said, ‘Did you do it?’ And he said, ‘No, I did not. Absolutely not,’ Trump told Reuters. “I then asked him a second time in a totally different way. He said absolutely not.”

That isn’t the point. The intelligence community has told Trump that Russia interfered. The president shouldn’t be inquiring — he should be informing Putin about the consequences of this unacceptable behavior. But Trump continues to dispute reality. “Somebody did say if [Putin] did do it, you wouldn’t have found out about it,” Trump added.

We are at risk of suffering outrage overload here. So many troubling things have happened, and Trump continues to make so many beyond-the-pale statements, that we are losing our capacity to respond to all of it with appropriate concern.

Meanwhile, the alarm bells clang. Trump, we are told, didn’t know about the meeting with Russian lawyer Natalia Veselnitskaya until a few days before it became public. Except, maybe, he did. “In fact, maybe it was mentioned at some point,” Trump acknowledged in a conversation with pool reporters — part of an off-the-record, then on-the-record encounter not included in the official White House transcript.

Was he talking about Russian adoption or the meeting itself? Unclear — but at this point, the White House deserves little presumption of honesty or full disclosure. The latest evidence: NBC News’s report that the Trump Tower meeting was also attended by a former Soviet counterintelligence officer. So much for Trumpian back-patting about transparency.

I hear the what-aboutists stirring. But what about Democrats and Ukraine? According to a January report in Politico, a Ukrainian American consultant to the Democratic National Committee “met with top officials in the Ukrainian Embassy in Washington in an effort to expose ties between Trump, top campaign aide Paul Manafort and Russia.” Problematic? Perhaps. But Ukraine is not a U.S. adversary. The scope of its reported involvement is far different from a Putin-directed effort to illegally hack emails to help elect Trump.

If there is one silver lining to this staggering news, it is that it serves to strengthen special counsel Robert S. Mueller III. Trump continues to cry “witch hunt.” Yet there can no longer be any doubt that there is something for Mueller to investigate. And even this supine Republican Congress would not tolerate his summary firing. Would it?

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