National Security Adviser H.R. McMaster has a sterling reputation. Now he’s putting it on the line to become a full-throated defender of President Donald Trump.

“I stand by my statement — the premise of the article is false that in any way the president had a conversation that was inappropriate or that resulted in any kind of lapse in national security,” he said during a press conference today, responding to a question about yesterday’s Washington Post report.

The article’s premise was that “President Trump revealed highly classified information to the Russian foreign minister and ambassador in a White House meeting last week.”

But McMaster never actually said what specific part of that “premise” was false. Instead, he chose to parrot the Trump administration’s go-to refrain in these situations — that the real issue here is leakers.

“Our national security has been put at risk by those violating confidentiality and by those releasing information to the press that could be used and connected with other information available to make American citizens and others more vulnerable,” he told reporters at the White House.

This might seem like a Post-said, White House-said scenario, but this is much, much more than that. Specifically, there are three main takeaways from the press conference:

One of the most respected generals of the past 20 years is laying his reputation on the line for the president. When repeatedly asked if Trump leaked classified information, McMaster refused to answer. McMaster did not deny that Trump decided to leak the information on his own without having first discussed doing so with intelligence officials.

McMaster is vigorously defending Trump

When Trump picked McMaster as his second national security adviser in the wake of the Michael Flynn debacle, the New York Times noted how the president had selected a “widely respected military strategist” to be his top national security staffer.

McMaster earned that respect. He is seen as somewhat of an icon in the military. As a brigade commander in Iraq, he became known as the “hero of Tal Afar” after kicking al-Qaeda out of its stronghold there. He also literally wrote the book, called Dereliction of Duty, on how dangerous it is when a president’s generals don’t stand up to him and do the right thing.

But now, by personally coming out and defending Trump’s actions, McMaster risks tarnishing his well-earned reputation.

At the press conference, he stated that “[i]n the context of that discussion” between the president and the Russian foreign minister, “what the president discussed was wholly appropriate to that conversation and is consistent with the routine sharing of information between the president and any leaders with whom he is engaged.”

“I was in the room, the deputy adviser for national security, Dina [Powell] was in the room, and none of us felt in any way that that conversation was inappropriate,” he added.

McMaster is putting his own personal credibility and professional judgment on the line here. And that’s risky — because when you take a closer look at his statements, it’s clear that he’s deliberately obfuscating what actually happened.

McMaster refused to answer the most important question

There was an important exchange between a reporter and McMaster during the press conference that’s worth reading in full:

QUESTION: General, when you came out after the story broke, you said that the president did not disclose any sources or methods. He did not reveal anything about military operations. Why were you denying things that were not even reported? The president revealed classified information by one of our allies in the Middle East, it is simply a yes or no question here, did he share that information? MCMASTER: We don't say what is and what is not classified. What I will tell you again is what he shared was appropriate. The story combined what was leaked with other information and then insinuated about sources and methods. So I wanted to make clear to everybody that the president in no way compromised any sources or methods.

Note what happened here: McMaster very pointedly did not deny that Trump shared classified information with the Russians. He merely claims that the information Trump shared was “wholly appropriate.”

Remember: McMaster stated that the “premise” of the Washington Post article is “false.” But at no point in the press conference did he actually refute the core premise of the article. Instead, he tried to make it seem like the intelligence shared was no big deal.

Then, right before leaving the press conference, he decided to make one additional point that he evidently thought would make Trump’s actions seem even more harmless. It did the exact opposite.

Trump “was not even aware of where this information came from”

Yes, that’s something the national security adviser actually said. Here’s the full quote:

He shares information in a way that is appropriate. And I should just make maybe the statement here that he [Trump] was not even aware of where this information came from. He was not briefed on the information, either.

McMaster told reporters that Trump shared intelligence with the Russians and he had no idea where it came from and was not briefed on it beforehand.

That’s big. It is now completely possible Trump gave intelligence to the Russians without any knowledge about how sensitive it was. In essence, Trump may have put a vital anti-ISIS source in danger without knowing the specifics of what he was revealing to Russia’s foreign minister and ambassador.

McMaster left after that, but questions remain. Most importantly, after the press conference it certainly appears that Trump did in fact reveal intelligence to the Russians — which he is technically allowed to do as president — but it might still have been intelligence that harms our anti-ISIS fight.

Here’s what is clear: McMaster is entering dangerous territory here by trying to refute this story and adopting the administration’s talking points. For the “hero” who once passionately argued for the importance of standing up for truth in the face of a president’s lies, that course of action seems decidedly unheroic.