“Russia, if you’re listening, I hope you’re able to find the 30,000 emails that are missing. I think you will probably be rewarded mightily by our press,” Donald Trump said, referring to messages deemed personal by Hillary Clinton and deleted from her private email server. To which Hillary Clinton replied, “Russia, if you’re listening, I hope you’re able to find Trumps tax returns and his several divorce settlements and his many non-disclosure agreements with former employees. What, Donald, can’t they disclose this?”

Of course, Clinton said no such thing. Instead, the consistently humorless campaign failed to treat Trump as a buffoon and instead issued a flat-footed rebuttal: “This has to be the first time that a major presidential candidate has actively encouraged a foreign power to conduct espionage against his political opponent,” Clinton’s senior policy adviser, Jake Sullivan, said in a statement. He added later: “This has gone from being a matter of curiosity, and a matter of politics, to being a national security issue.”

No, no, Jake, the national security issue is the prospect of Trump in the White House. In the meantime, his ludicrous statements ought to be treated as the braying of a jackass. The way to hurt Trump is to ridicule him. He is a man of immense pride, a pompous bloviator and a locker-room towel-snapper. Either ignore him or ridicule him. Formal rejoinder ought to be reserved for adults.

Republican presidential nominee Donald Trump speaks at a campaign event at Trump Doral golf course in Miami on Wednesday. (Carlo Allegri/Reuters)

Now to the matter of Trump’s tax returns. He will be the first presidential candidate in a long time who did not release his tax returns. He says that’s because he’s being audited. Maybe. But what about tax returns for all the previous years? All being audited? Not likely.

No, the reason he will not release his tax returns is that they probably contain embarrassing information. The first and most trivial revelation would be that his net worth is not anywhere near what he says it is. The second is that it might show he paid precious little in taxes. This is the virtue of owning real estate. You deduct, and you depreciate. In a sense, the money is not made by the property. It’s made by the tax code. Third, Trump may not have given a dime to charity. His tax returns will show him to have not a charitable bone in his body.

Clinton might do well to emulate Franklin D. Roosevelt. In 1944, he mocked Republican attacks on him by citing a rumor about his dog, Fala. “Republican leaders have not been content with attacks on me, or my wife, or on my sons. No, not content with that, they now include my little dog, Fala. Well, of course, I don’t resent attacks, and my family don’t resent attacks, but Fala does resent them. You know, Fala is Scotch, and being a Scottie, as soon as he learned that the Republican fiction writers in Congress and out had concocted a story that I’d left him behind on an Aleutian island and had sent a destroyer back to find him—at a cost to the taxpayers of two or three, or eight or twenty million dollars—his Scotch soul was furious. He has not been the same dog since. I am accustomed to hearing malicious falsehoods about myself … But I think I have a right to resent, to object, to libelous statements about my dog.”

That was September. In November, FDR won a fourth term.