On Thursday, Mitt Romney will join the Senate. And he’s decided to join the great deliberative body in a very high-profile way.

The former Massachusetts governor and senator-elect from Utah published an op-ed Tuesday night in The Washington Post arguing that President Trump’s character “falls short.”

"The Trump presidency made a deep descent in December,” Romney wrote, citing the departures of Defense Secretary Jim Mattis and Chief of Staff John F. Kelly, the appointment of less experienced Cabinet replacements and the destruction of U.S. alliances. “On balance,” Romney added, Trump’s "conduct over the past two years, particularly his actions this month, is evidence that the president has not risen to the mantle of the office.”

There have been two prevailing and very polarized reactions to the op-ed.

One is that Romney is setting himself up to lead the anti-Trump wing of the Republican Party (such as it is currently constituted) . ..

. . . and the other is very understandable skepticism that he’ll actually put his conduct where his mouth is.

The argument for the latter is evident. Trump’s top critics in the Senate GOP — Jeff Flake (Ariz.), Bob Corker (Tenn.), Ben Sasse (Neb.) and, for a time, Lindsey O. Graham (S.C.) — talked a big game but did little to impact Trump’s actions. The first two opted for retirement, with Flake waving a white flag in the face of Trumpism and really only using his legislative prerogatives toward the end of his tenure. Graham, once critical, is now a top Trump ally who occasionally criticizes his foreign policy. All have regularly voted with the president’s priorities.

Romney’s history with Trump suggests he could follow a similar path.

Romney criticized Trump in more severe terms than just about anybody in 2016, even after Trump was the de facto GOP nominee. But he’s also been happy to play ball and accept his help. As the GOP presidential nominee in 2012, he flew out to accept an endorsement from Trump, then in the throes of birtherism. After Trump was elected president, Romney interviewed to be Trump’s secretary of state.

When Romney decided to run for Senate, he accepted Trump’s endorsement again and backed off his previous criticisms of the leader. At a debate three months ago, Romney was asked three times whether he still thought Trump was a fraud and a phony. "I’m going to talk about the future,” he responded.

His op-ed seems, in part, to be an effort to explain his many about-faces. In the piece, Romney emphasized twice that he’s particularly appalled by this past month of Trump’s presidency. This may be true, but it’s also an extremely convenient line. After all, Trump’s Cabinet has been trending toward less-experienced yes-men for a long time, a phenomenon that accelerated after the 2018 election. Trump’s character has been pretty consistent throughout. Romney’s point about Trump and the damage to U.S. alliances is also something you could have said for much of the past two years.

But that doesn’t mean Romney will necessarily fail to act as a check on Trump’s power. Even if Romney chose political expediency before, he could feel this is his chance to effect change, now that he’s actually got a Washington job. It’s worth entertaining the idea that Romney truly believes his past Trump criticisms and now wants to do something about them — or at least try. “I do not intend to comment on every tweet or fault,” Romney writes. “But I will speak out against significant statements or actions that are divisive, racist, sexist, anti-immigrant, dishonest or destructive to democratic institutions.”

Romney has a bigger platform than any of the four GOP senators mentioned above. He also has more experience as a national voice. He may view this as a chance to right the ship in the GOP and the country — or even set himself up for another presidential bid if Trump and Trumpism falters.

“I find this so troubling, and I know a lot of folks are saying, ‘Mitt, just get off your high horse on this and get behind the guy,'” Romney said back in June 2016. “But these things are personal. I love this country. I love the founders. I love what this country is built upon and its values, and seeing this is breaking my heart.”

If Romney believes what he said in 2016, anything except very vocal criticism of Trump and bona fide actions will expose Romney as just another mealy-mouthed politician.