National Security Advisor H.R. McMaster spoke at the White House on May 15 and denied recent reporting that President Trump revealed classified information in a meeting with Russian officials. (Reuters)

On Monday evening, national security adviser H.R. McMaster put his reputation, honed over decades, on the line to issue a non-denial denial — claiming that The Post’s story was wrong because President Trump did not disclose to Russia’s foreign minister and ambassador “sources and methods.” The Post did not say anything of the sort, but rather, accurately reported that Trump revealed highly classified material obtained from an ally — the disclosure of which would endanger our relationship with our ally and jeopardize the means by which we obtained the information.

As he apparently did with obstruction of justice regarding the firing of James Comey, the president “confessed” in a tweet this morning, saying, “As President I wanted to share with Russia (at an openly scheduled W.H. meeting) which I have the absolute right to do, facts pertaining to terrorism and airline flight safety.” He added: “Humanitarian reasons, plus I want Russia to greatly step up their fight against ISIS & terrorism.” In one fell swoop, Trump revealed his abject unfitness and exposed McMaster, Secretary of State Rex Tillerson and deputy national security adviser Dina Powell — all who personally attempted to knock down the story — as dishonest hacks.

It is not unreasonable to ask whether McMaster, a lieutenant general who was previously seen as one of the few credible voices in the administration, can now serve the country and protect it from an unfit president only by resigning. “You know, that is a hard question to answer. Of course, I would not have gone in to begin with, but once in, people have conflicting loyalties, I think,” says former ambassador to Turkey Eric Edelman. “One is to the nation and trying to ensure that the country remains secure and that the normal business of government is attended to, the other, of course, is to their conscience.” He adds, “H.R. got sent out yesterday because of his stature and the respect in which he is held for honesty and integrity. Of course, what he did has ended up sullying his reputation and undercutting his standing. At this point, I think the calculus has to be how can my resignation actually help bring about a positive result?” He concluded, “If he just quits to show he really is pure, doesn’t that seem like an act of moral vanity? Perhaps the right thing is to wait until a resignation becomes part of a push to either force a resignation or the invocation of the 25th Amendment.”

H.R. McMaster (Susan Walsh/Associated Press)

On the other hand, Tillerson — who just Sunday claimed he would never sacrifice his “values” — has shown himself to be of little value to the country. His greatest contribution to the country would now be to quit.

Whatever they decide, three public servants have jettisoned their credibility in service of an unfit president. Frequent Trump critic and former State Department official Eliot Cohen writes:

Now, what Tillerson, Powell, and McMaster said are not quite lies, but they are the kind of parsed half-truths that are as bad, and in some cases worse. This is how one’s reputation for veracity is infected by the virulent moral bacteria that cover Donald Trump. Friends will watch, pained and incredulous, as they realize that one simply cannot assume that anything these senior subordinates of the president say is the truth. And having stretched, manipulated, or artfully misrepresented the truth once, these officials will do it again and again. They will be particularly surprised when they learn that most people assume that as trusted subordinates of the president, they lie not as colorfully as he does, but just as routinely. Perhaps the worst will be the moment when these high officials can no longer recognize their own characters for what they once were.

What is more, they are now useless surrogates. The patina of independence and integrity has dissolved, revealing them to be no more reliable than Sean Spicer.

Trump’s candor underscores how clueless he remains about his egregious betrayal of an ally, an act that will diminish U.S. access to intelligence and potentially endanger those who provided the underlying intelligence. Republicans have not been moved to date to take on Trump, in effect doing nothing to defend the country against a president who poses a danger to our institutions and security. Now would be the appropriate time to get off the Trump train and name a select committee whose job it will be to determine whether Congress should move ahead to impeachment. If they do not act now — and I have little reason to believe they will — they do not deserve to hold power. What is more, they will leave a legacy of complicity in whatever damage Trump causes before leaving office.