When the story of Trump University came out, some of Donald Trump's critics began referring to him as a con artist. Trump is extraordinarily thin-skinned; he can't seem to let any attack roll off him. So last Tuesday he spent lots of time explaining why his various branding ventures — not just Trump U but also Trump Steaks, Trump Vodka, and many others — were not cons, but the most premium-quality experiences its customers ever had. But I suspect Trump wasn't all that insulted by being called a con artist; his business is about branding and myth-making, and he knows that there's a fine line between a con man and a great salesman. What Trump really couldn't tolerate is being the guy on the other end of the con: a sucker.

The fear of being a sucker seems to be one of the prime motivating forces in Trump's entire life, one that shapes not only his business career, but how he views the country. In the recent biography Never Enough, author Michael D'Antonio singles out an event that occurred when Trump was a freshman in college as a seminal moment. Attending the opening of the Verrazano-Narrows Bridge with his father, Trump saw how the elderly architect who designed the bridge, Othmar Ammann, was ignored by developer Robert Moses during the ceremony, not listed among the people Moses thanked. "The lesson Trump took away was that somehow Ammann was to blame for being overlooked," D'Antonio writes. "Trump decided he would remember the incident because 'I don't want to be made anybody's sucker.'" And suckers are worthy of nothing but contempt.

That's what animates Trump's deal-making as he sees it — is he the sucker, or is the other guy? A sucker is someone who doesn't understand the balance of power, who gets taken advantage of by someone smarter, who's humiliated, emasculated, and ridiculed. It isn't a surprise that Trump was drawn to the casino business, where every day millions of dollars are made by casino owners taking money from suckers who don't understand that the game is rigged against them.

With that in mind, listen to how Trump talks about America and how it relates to other countries. For Trump, relations between countries, particularly when it comes to trade, are really just a question of who's the sucker. And as he sees it, it's us.

For instance, you could view China or Mexico as nations that have pursued a growth model based on low-wage manufacturing, utilizing the comparative advantage they enjoy at this point (lots of people eager to work for not much money). But Trump sees only a con game, one where not only are we the marks, but — and this is critical — they're laughing at us. "If you don't tax certain products coming into this country from certain countries that are taking advantage of the United States and laughing at our stupidity," he said at Thursday's debate, "we're going to continue to lose businesses and we're going to continue to lose jobs."

The idea that trade is not exactly a zero-sum game — for instance, that American consumers benefit from being able to buy imported goods at low cost — is not part of his calculation. Trump brings up the idea of other countries laughing at us so often that in January, The Washington Post charted over 100 instances of Trump asserting that others are laughing at America, from China (the biggest laugher, apparently) to OPEC to Mexico to Iran. Often he'll just say that "the whole world" is laughing at us, which is the sucker's ultimate fear: not just that you got scammed, but that everyone knows it, and points their fingers at you in mockery.

When Mitt Romney gave a speech earlier this month attempting to dissuade Republicans from voting for Trump, he said, "He's playing members of the American public for suckers: He gets a free ride to the White House, and all we get is a lousy hat." Romney may be closer to Trump in this way than you'd think; in 2012, when he got asked about his low tax rate, he would say, "I pay all the taxes that are legally required and not a dollar more. I don't think you want someone as the candidate for president who pays more taxes than he owes." In other words, only a sucker wouldn't hire a team of accountants to find every last loophole in the tax code, and how could someone like that be president?

I can't help but think that there's a part of Donald Trump that doesn't really mind when someone like Romney calls him a con man, so long as nobody takes it too seriously. Sure, he doesn't want Americans to think that he's just running a scam on them. But there's one thing a lot worse than being the one pulling the con, and that's being the one who got conned. Because then people might laugh at you.