Free trade agreements “have been disastrous” for the United States, the candidate said, and have sent jobs to Mexico and China. “I will stop it by renegotiating all of the trade agreements that we have.”

It sounded like just another threat from Donald Trump to “rip up those trade deals” and “make really good ones” instead. Such a policy could set off a global trade war and impoverish millions.

But the candidate who said this was Bernie Sanders, April 1 in New York. And that’s no coincidence: He and Trump are peas in a pod.

In their political philosophy and temperament, they couldn’t be more opposite. Trump is a billionaire with strongman tendencies who preys on the weak and has run the coarsest political campaign in modern memory. Sanders is a socialist and champion of the little guy who talks with compassion about the poor and refuses to get into the gutter.

But the two are the yin and yang of outlandish policy proposals. Both men — and to a great extent Ted Cruz, too — have grounded their platforms in fantasy.

Trump talks about deporting all 11 million illegal immigrants — and yet, contradictorily, about seizing the remittances these immigrants send home so he can force Mexico to pay for a border wall. He says he’ll eliminate the $19 trillion federal debt in eight years — easy peasy — a pledge the Post’s fact checker, Glenn Kessler, calls “wildly impossible” and “insulting [to] the intelligence of Americans.”

Sanders, like Trump, would throw out all trade deals — and then renegotiate deals only with countries that have wages comparable to the United States’ — a policy that could, Vox’s Zack Beauchamp wrote, “devastate economies in the developing world.” Sanders promises health care and free college for all and has plans that would increase the size of the federal government by 50 percent — no sweat.

Cruz agrees with Trump on deporting all illegal immigrants. For good measure, he vows to eliminate the IRS and to gut the federal income tax, then have an astronomical increase in military spending.

This presidential race is typically cast in conventional terms: Democrats vs. Republican. But it might be better cast as the responsible vs. the reckless. The reckless — Republicans Trump and Cruz and Democrat Sanders — are exciting voters by promising things that will never happen. The responsible — Democrat Hillary Clinton and Republican John Kasich — are failing to fire up the masses because they are acknowledging the limits of the real world.

This is corrosive. The pie-in-the-sky proposals from Trump, Sanders and Cruz build up unrealistic hopes among their followers — and will fuel cynicism when those hopes, inevitably, are not met.

I asked Maya MacGuineas, head of the nonpartisan Committee for a Responsible Federal Budget, to rank the candidates in terms of irresponsibility. Trump was tops, with Sanders and Cruz competing for second place. The Sanders proposals would increase federal spending most, but in second and third place on that measure are Trump and Cruz — because their huge tax cuts would cause the debt, and interest payments, to soar. Clinton and Kasich would grow government least.

MacGuineas’s group calculates that Sanders would increase government spending to unimaginable levels: to as much as 35 percent of gross domestic product, from the current 22 percent. His initiatives would cost up to $28 trillion, and even after massive tax increases would add as much as $15 trillion to the national debt.

Trump, too, would increase the national debt over a decade by as much as $15 trillion more than under current law, because he doesn’t pay for the tax cuts he envisions. To pay for those, spending would need to be cut by as much as 80 percent. Among Trump’s risible proposals to cut costs: He claims he would save $300 billion a year from reducing waste in a prescription-drug program, but the entire program costs only a third that much. To pay down the debt over eight years, without cutting Social Security, he would have to cut government by 93 percent.

Then there’s Cruz, who would increase the debt over the decade by an additional $12.5 trillion above current policies, though MacGuineas’s group says the number could go as high as $21 trillion.

Clinton and Kasich, by comparison, are “very fiscally responsible,” MacGuineas said. Hence, the reckless party vs. the responsible party. Cruz and Trump are “outlandish in the amount of revenue they’re talking about cutting,” while Sanders talks about “growing government by 50 percent without a penny for the debt. That’s not only unrealistic, that’s dangerous.”

These proposals aren’t dangerous because they could actually happen; they can’t. They’re dangerous because supporters of these three men, believing these fantasies masquerading as policies, are headed for disillusionment.

Twitter: @Milbank

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