What is Donald Trump hiding in his tax returns?

On Wednesday, Trump’s campaign manager, Paul Manafort, told CBS This Morning that Trump will not release his tax returns before the November election.

CBS's Norah O'Donnell asked Manafort, “Paul, I saw that Trump tweeted yesterday that he has ‘zero investments in Russia.’ But does Russia have investments in Trump? Would Mr. Trump be willing to release his taxes to provide transparency on this issue?”

Manafort responded, “Mr. Trump has said that his taxes are under audit. He will not be releasing them. It has nothing to do with Russia, it has nothing to do with any country other than the United States and his normal tax auditing process. That issue will be dealt with when the audits are done.”

O’Donnell pressed, “So to be clear, Mr. Trump has no financial relationships with any Russian oligarchs?" Manafort answered, "That’s what he said, that’s what I said. That’s obviously what our position is."

Among others, Pulitzer-Prize winning conservative columnist George Will, who left the GOP after a lifetime as a member because of Trump’s nomination, has speculated that Trump is hiding his returns because there might be something amiss. Responding to Fox News Bret Baier, who pointed out that the Democratic leadership had speculated on the possibility of Trump’s tax returns revealing something about Russian connections, Will replied, "Well, it's the sort of thing we might learn if we saw the candidate's tax returns. Perhaps one more reason why we're not seeing his tax returns — because he is deeply involved in dealing with Russian oligarchs and others. Whether that's good, bad or indifferent, it's probably the reasonable surmise."

Trump is the first major party nominee in over forty years not to release his personal tax returns. Manafort and Trump’s excuse that Trump won’t release the returns because of the current audit holds little weight; Richard Nixon released his returns in 1973 despite being audited.

Manafort and Trump’s excuse that Trump won’t release the returns because of the current audit holds little weight; Richard Nixon released his returns in 1973 despite being audited.

Mitt Romney, who released his 2010 tax returns in January of 2012 and his 2011 tax returns as soon as they were completed, in September of 2012, slammed Trump back in May, writing:

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.