There’s something soooo familiar about this. Oh, right — it’s the same attack Romney launched on Trump back in February, right down to the insinuation that there’s a “bombshell” lurking in Trump’s taxes that he’s trying to hide.

What game are you playing, Mitt Romney?

It is disqualifying for a modern-day presidential nominee to refuse to release tax returns to the voters, especially one who has not been subject to public scrutiny in either military or public service. Tax returns provide the public with its sole confirmation of the veracity of a candidate’s representations regarding charities, priorities, wealth, tax conformance, and conflicts of interest. Further, while not a likely circumstance, the potential for hidden inappropriate associations with foreign entities, criminal organizations, or other unsavory groups is simply too great a risk to ignore for someone who is seeking to become commander-in-chief.

Mr. Trump says he is being audited. So? There is nothing that prevents releasing tax returns that are being audited. Further, he could release returns for the years immediately prior to the years under audit. There is only one logical explanation for Mr. Trump’s refusal to release his returns: there is a bombshell in them. Given Mr. Trump’s equanimity with other flaws in his history, we can only assume it’s a bombshell of unusual size.

It’s one thing to be #NeverTrump, it’s another thing for a party’s reigning nominee to interrupt a week’s worth of “Will the GOP unify?” storyline to declare that the presumptive nominee has disqualified himself. I’m going to resist the temptation to write my 8,000th “Is Romney running?” troll post and instead wonder if maybe this is how he’s going to try to take Trump down instead, by sporadically handing Democrats ad-ready soundbites to use against Trump. I know, I know — most Republicans don’t care what Romney thinks. A few do, though, and even some independents would marvel at a party’s last nominee declaring the current one too ethically dubious to be trusted with the presidency. It’s a blow to the “unity” message, and deliberately so.

John Fund has a piece up at NRO speculating about what might be in those returns that Trump doesn’t want people to see. A lower-than-expected net worth? Small charitable donations, or perhaps donations to the “wrong” charities? Ties to criminal organizations? Something else? Fund wonders outright what the delegates in Cleveland might do if Romney turned out to be right about a bombshell hidden in the returns if it burst before the convention. That may be another Romney angle in attacking today, to plant another seed of doubt in the minds of anti-Trump delegates. But let’s say it happened, and that somehow Trump’s returns were illegally leaked. How would Trump handle it? This bit from Fund’s piece rings completely true:

A friend of Donald Trump’s recently approached him to suggest that he will eventually have to release his tax returns, as every presidential nominee has for decades. The friend told Trump that he should do it before the GOP convention to ensure everyone can process what’s in the returns and help make any revelations “old news” by November. If Trump didn’t do that, he was warned, the odds of politicized leaks from his returns were high, citing several examples from the Obama era, including the illegal leaking of some of Romney’s tax information by the IRS in 2012.

“What will you do if the returns come out as part of an October surprise?” Trump was asked. Trump pondered the question and replied, “I’ll say they aren’t mine.” That stunning answer is the essence of Donald Trump. “It’s exactly what I’d expect him to say,” Fox Business’s Charlie Gasparino, who has known Trump for decades, told me.

Indeed he would, and thanks to the ineffable sleaziness of the Clintons, a lot of people would believe him. Maybe that’s part of Romney’s game too. A squeaky clean figure like him teasing the possibility of a “bombshell” suggests that he knows something the rest of don’t. If something comes out, today’s statement will be used to bolster the credibility of the leak when Trump denies it. “Romney knew!”

Trump put out this statement this afternoon on Twitter. The returns are coming, maybe?

Here he is telling Hugh Hewitt last year, before he got in the race, that he’d release his returns. Worth noting, though: When Harry Reid smeared Romney in 2012 by accusing him, baselessly, of failing to pay his own taxes, Trump came to Romney’s defense.

Update: The backlash begins.