President Trump fears embarrassment more than anything, and nothing would embarrass him more than proof that he isn't as rich as he says he is.

Of all the strange things Trump has done, one of the strangest was his decision in 2011 to be roasted on Comedy Central. Being ridiculed on TV for an hour is hard for any normal human being, but especially hard for narcissists. According to The Huffington Post, Trump stipulated that there be no jokes about his bankruptcies or suggestions that he exaggerated his wealth — in other words, no truths about his finances. Everything else was fair game.

Snoop Dogg remarked, "Donald say he wants to run for president and move on into the White House. Why not? It wouldn't be the first time you pushed a black family out of their home."

Anthony Jeselnik told Trump that the only difference between him and Michael Douglas' character in the movie Wall Street "is that no one's going to be sad when you get cancer."

Trump consented to a joke comparing his hair to a wet raccoon because the punchline involved him being worth $7 billion, unlike a wet raccoon.

Why did Trump subject himself to this? Two reasons: an hour on TV devoted to him and $400,000. Getting paid to hear how rich you are was a deal that Trump couldn't refuse.

Trump wants two things in life: to be wealthy and to be perceived as wealthy. He derives his self-worth from his net worth. "Part of the beauty of me is that I am very rich," he said in 2011. At the time, Trump was considering a presidential run, which would entail financial disclosures. "I look very much forward to showing my financials," Trump said, "because they are huge." Two years later, he claimed his net worth was "substantially over $8 billion, with a lot of cash, and everybody knows it," but declined to provide any details because, as he said, everybody already knew them.

As you know, you don't know anything about Trump's tax returns — and he's determined to keep it that way. In April, Trump sued Deutsche Bank and Capital One to prevent them from responding to congressional subpoenas. This summer, he sued New York state officials and the House Ways and Means Committee to keep his tax returns secret. In addition, he and the Republican National Committee successfully sued California over its law requiring presidential candidates to disclose five years of their tax returns to qualify for the state's primary ballot, a law they called a "naked political attack against the sitting president of the United States."

Nobody knows what Trump's tax returns would reveal. It's possible they involve instances of fraud, financial malfeasance, and/or dealings that compromise U.S. national security, but even if they don't — even if they show Trump to be a law-abiding, patriotic taxpayer — they are likely to be highly embarrassing to the president. How do I know? Because Trump's own people say so.

White House acting Chief of Staff Mick Mulvaney said Democrats want to "embarrass" Trump by getting his tax returns. Why would Trump be embarrassed about his tax returns? "That's what they want to know," Mulvaney said, making no sense.

Trump hides his tax returns the way he accused Barack Obama of hiding his birth certificate. As a presidential candidate, Trump refused to share them on the grounds that the IRS was auditing him. Then, as president, he and his aides claimed that voters didn't want to see them and therefore no one ever should. Now his lawyers argue that any attempt to attain them lawfully constitutes "presidential harassment."

"They're just doing this to make the president look bad," Mulvaney said. Mulvaney says he hasn't seen the president's tax returns. Like the rest of us, he doesn't need to. If the president's tax returns made him look good, we would have seen them already, just as we saw Kim Jong Un's "beautiful" letters to "Your Excellency."

Trump tells us everything we don't want to know (the number of ballrooms at his resorts, for example) and nothing we need to know (like who is paying for them). Worse, he sues people who endeavor to uncover the truth for fear that it will inconvenience or embarrass him.

It's hard to trust a man who spends more time talking about money than earning it. Yet we are supposed to believe that a man who is vain enough to brag about his wealth is too modest to furnish proof of it. Trump talks about his tax returns the way boys talk about their Canadian girlfriends: They're real and beautiful, but you can't see them.

Which is why we should. If we can't remove Trump from office, we can do the next best thing and embarrass him while he's there.

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