McMaster’s decision to take the position of national security adviser was far more complicated than the choice that faced many others who went to work for Trump. As an active military officer, turning down a request from the commander-in-chief goes against the very ethos of the military, and McMaster no doubt felt that the call of duty should supersede any reservations about working for a leader as undisciplined and as odious as Trump.

But if we’ve learned anything about Donald Trump, it’s that he debases all those who are pulled within his orbit — and as the past week has shown, McMaster is no different.

When President Trump selected General H.R. McMaster to replace Michael Flynn as his national security adviser, the decision was met with near-universal praise. McMaster was a talented military leader and scholar who would not be intimidated by his proximity to power, or so said those who knew him. He would be the proverbial “adult in the room” on Trump’s national security team.

The fear, however, was that McMaster would be unable to stay above politics and would become corrupted by Trump, and that’s precisely what has happened.


Last Friday, McMaster was trotted out to the White House briefing room to offer a preview of President Trump’s upcoming foreign trip. With the White House in crisis over the firing of FBI Director James Comey, his presence was really about diverting attention from that story with the one man in the administration who maintains a semblance of credibility. But that McMaster had become a political dupe seemed not to dawn on him, as his briefing veered disquietingly into the realm of politics and public relations.

McMaster suggested that Trump’s visit would “bring a message of tolerance and of hope to billions” in the region. Literally no one believes this, particularly since Trump has spent two years engaged in some of the most unseemly anti-Muslim xenophobia of any president in modern American history.


More disturbingly, McMaster took a back-handed slap at the last administration in claiming that there is a “perception” in the region “that America had largely disengaged from the Middle East.” Rather than pointing out that this perception is false — and above all is a political attack on former president Barack Obama — McMaster said Trump’s “galvanizing” leadership would bring “leaders across the region” back together.

But the far more enduring damage to McMaster’s credibility came this week, amid allegations that the president had leaked classified information to the Russian foreign minister and Russian ambassador to the United States.

McMaster again took the lead in defending the president, declaring in a press statement that the story “as reported is false,” which he claimed to know because he was in the room with Trump and the Russians. He also said that “at no time were intelligence sources or methods discussed” in the meeting, which denied a charge not actually made in a Washinton Post article. This is a classic non-denial denial, intended to mislead.

By the next morning, Trump had torpedoed McMaster’s credibility when he took to Twitter and tacitly confirmed the story’s veracity by noting that he had an “absolute right” to share classified information with the Russians.

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.... — Donald J. Trump (@realDonaldTrump) May 16, 2017

...to terrorism and airline flight safety. Humanitarian reasons, plus I want Russia to greatly step up their fight against ISIS & terrorism. — Donald J. Trump (@realDonaldTrump) May 16, 2017

Yet, McMaster was back the next morning, claiming in a White House press briefing room that it was “wholly appropriate” for Trump to leak classified information to representatives of a country that directly interfered in the US presidential election. But when pushed as to why administration officials had scrubbed the offending material from internal memos about the call and why the heads of the CIA and NSA had been alerted to Trump’s leak, McMaster weakly claimed this was done out of an “abundance of caution” and that he hadn’t even asked his aides why they had done it.


McMaster even took the same line of argument that Trump’s enablers have used in defending the president — that the leaks highlighting Trump’s incompetence, dishonesty, and corruption are worse than these crimes themselves.

At best, McMaster has spent the past week dissembling. At worst, he’s lying.

By crossing that line, McMaster reduced himself to being little better than the vacuous talking heads on cable news networks who slavishly defend every Trump action, no matter how awful or damaging.

What makes McMaster’s recent behavior so depressing is that he is an officer who has long shown a willingness to speak truth to power — a trait not often widely shared or praised in a hierarchical institution like the US military.

McMaster is legendary for pushing back to his military superiors and for being a voice of dissent. That’s the role that many believed he would fulfill as Trump’s national security adviser. Instead, he’s become precisely the person he once railed against.


Indeed, McMaster is perhaps most well-known for his book “Dereliction of Duty,” which chastised the US military for its failure to be honest with their civilian leaders — and the American people — about the unfolding tragedy in Vietnam. In the epilogue to that book, McMaster concludes that it was a “uniquely human failure” and that these “failings were many and reinforcing: arrogance, weakness, lying in the pursuit of self-interest, and, above all, abdication of responsibility to the American people.”

Perhaps McMaster should take a quiet moment to reflect on those words.

Michael A. Cohen’s column appears regularly in the Globe. Follow him on Twitter@speechboy71.