Rubio makes a powerful case against Trump (while endorsing him)

Republican presidential candidate Marco Rubio and rival candidate Donald Trump argue at the same time at the debate in Detroit, Mich., March 3, 2016. (Photo by Jim Young/Reuters)
Republican presidential candidate Marco Rubio and rival candidate Donald Trump argue at the same time at the debate in Detroit, Mich., March 3, 2016.
About a month ago, Sen. Marco Rubio (R-Fla.) was reminded that during his failed presidential campaign, he told voters that Donald Trump shouldn't be given access to nuclear codes because he lacked the necessary judgment and temperament. "I stand by the things that I said," Rubio replied, shortly before saying he'll support Trump's candidacy anyway.
Yesterday, the Weekly Standard's John McCormack talked to the Florida senator about the same issue, and received a very similar response.

One month after announcing his support for Donald Trump, Marco Rubio still believes that the presumptive GOP nominee is unfit to be commander-in-chief. "I stand by everything I said during the campaign," the Florida senator told THE WEEKLY STANDARD on Thursday when asked if he still believes Trump cannot be trusted with access to the country's nuclear weapons codes. During the campaign, Rubio said that Trump was "dangerous" and that we must not hand "the nuclear codes of the United States to an erratic individual."

Rubio doesn't seem to understand why this posture is untenable. Perhaps I can help.
Stepping back, one of the challenges for Republicans with the controversy surrounding Judge Gonzalo Curiel is that the entire story is a trap of sorts from which there is no easy escape. If GOP officials acknowledge Trump's racism, they're effectively saying they want a racist in the White House. If they deny Trump's racism, they look like cowards. It's why so many GOP officials have tried to get creative while walking a fine line, with varying degrees of success.
Rubio's challenge, meanwhile, is every bit as dramatic, if not more so.
Here's a sitting U.S. senator, who claims an expertise on matters of foreign policy and national security, who has insisted, repeatedly and publicly, that his party's presidential candidate simply cannot be trusted to be responsible with the planet's most dangerous weapons.
Rubio could, at this point, avoid a trap by walking back what he said, explaining as many have before that comments made in the heat of a primary can be hyperbolic, and saying he no longer thinks so poorly of his former rival. Except, the senator isn't saying that at all. On the contrary, even while maintaining his support for Trump, the far-right Floridian is sticking to each of his previous positions.
In the Curiel matter, Republicans are awkwardly searching for a middle ground, but in this case, Rubio is making no such effort, preferring instead to endorse two contradictory positions.
It's political cognitive dissonance on a scale to which we're unaccustomed: Marco Rubio doesn't believe Donald Trump should be president. Marco Rubio also believes Donald Trump should be president. The GOP senator genuinely believes American voters should take both of his positions seriously.
But we can't in large part because Rubio doesn't seem to take his own positions seriously.