House Intelligence Committee Chair Devin Nunes (R-Calif.) and Ranking Democrat Adam Schiff (Calif.) expressed doubt, March 15, about President Trump's claim of a 2016 wire tap at Trump Tower. (Reuters)

If there is one man on Capitol Hill whom President Trump might want to stay in the good graces of, it's Rep. Devin Nunes (R-Calif.). Nunes is the head of the House Intelligence Committee, which is in charge of investigating Russia's role in the 2016 presidential race — you know, the one Democrats think could prove collusion between the Trump campaign and a foreign power.

And until this week, that was a good setup for Trump. Nunes had been a member of his own transition team, after all, and he seemed to go out of his way to defend Trump — in a way few others did, frankly.

That may no longer be the case.

Nunes delivered a reasonably strong rebuke of Trump on Wednesday for his tweet that President Barack Obama had wiretapped Trump Tower, saying that if the tweet were to be taken literally, “clearly the president was wrong” (meaning Trump). The comment came a couple of days after Nunes threatened to subpoena the Trump administration for not turning over evidence related to Trump's claim.

As I argued Tuesday, Nunes seems to be fed up with this story line, and he's suddenly willing to wield his authority in a way that Trump probably doesn't love. Or, at the very least, Nunes is now bowing to the reality of Trump's wayward and still evidence-free conspiracy theory.

And that's a clear reversal from where Nunes has been in recent weeks.

A month ago, when then-national security adviser Michael Flynn was in hot water, Nunes gave him a big — if ill-timed — vote of confidence. He said Flynn should not step down mere hours before Flynn was forced to do so.

“No, I don't,” Nunes told Fox News Channel's Neil Cavuto. “I have great confidence in Mike Flynn. He’s probably the best intelligence officer of his generation. And Neil, he’s being attacked maliciously by the press, which is not uncommon in this town.”

Two weeks later, Nunes shrugged off the idea that Trump might have asked Flynn to signal to the Russian ambassador to the United States that Trump would ease Obama's sanctions once Trump was in office. Even discussing those sanctions during Trump's transition period risked violating the law, and Flynn later misled the White House about it, leading to his resignation.

At the time, Nunes said he didn't think it was even plausible that Trump had directed Flynn to talk sanctions because Trump was so busy — a curious argument, in my mind.

“I would find that hard to believe because they were so busy, and I think these conversations were all very short,” Nunes said.

Then, last week, Nunes seemed to pooh-pooh the same tweets he addressed Wednesday, suggesting that Trump should be excused for being a newcomer to politics and not having lawyers review every tweet. It was truly a wide-ranging defense.

“The president is a neophyte to politics,” Nunes said. “He’s been doing this a little over a year. And I think a lot of the things that he says, you guys sometimes take literally. Sometimes he doesn’t have 27 lawyers and staff looking at what he does — which is, I think, at times refreshing and at times can also lead us to have to be sitting at a press conference like this, answering questions that you guys are asking. But at the end of the day, I think tweets are a very transparent way for a politician of any rank to communicate with their constituents. So I don't think we should attack the president for tweeting.”

Fast forward to Wednesday, and Nunes has now delivered perhaps the most significant contradiction to the White House's ongoing claim — which Trump apparently still subscribes to — that Obama surveilled him somehow.

We'll see where Nunes's relationship with Trump goes from here, but he's in a position of power. And perhaps he's finally realizing that.