Before Donald Trump began to slur his words and concoct fake verbs like “tolerize,” he declared yesterday that “as long as I’m president of the United States, Iran will never be allowed to have a nuclear weapon…Their pursuit of nuclear weapons threatens the civilized world. We’ll never let that happen.”

Great. If that’s what he wants, perhaps he’d take a deal that compelled Iran to cut its uranium-enriching centrifuges by nearly 75 percent until the late ’20s; to convert a giant enrichment site to peaceful purposes (including the production of medical isotopes); to provide access to foreign scientists; to submit to ongoing international inspections; and to produce so little fissile material that even if Iran seemed on track to build one bomb – what our negotiators call a “breakout” – America and its allies would have a full year to initiate a crackdown. If Iran were to OK all those restrictions, and abide by them, wouldn’t that be a great way to deescalate nuclear tensions for the remainder of his tenure?

Oh wait! Those were the terms of the historic nuclear deal that Trump tore up two years ago.

The same deal that 63 percent of Americans didn’t want him to tear up. The deal that was endorsed by the Trump’s Joint Chiefs of Staff, Trump’s Defense secretary, Trump’s Secretary of State, the International Atomic Energy Agency, and all our western allies. The deal that was working so well in 2017 and 2018 that Trump’s director of national intelligence and CIA director both told Congress that Iran was in full compliance. Iran had destroyed the core of a reactor that could’ve been used to make weapons-grade plutonium. It had placed two-thirds of its centrifuges under international monitoring. It had reportedly eliminated 97 percent of its enriched uranium stockpile. The deal wasn’t perfect, but there was measurable progress where once there was none.

Alas, the deal had one fundamental problem: It was a signature achievement for Barack Obama. So of course it had to go.

Obama had embraced the credo best expressed in Godfather II by Michael Corleone: “Keep your friends close, but your enemies closer.” If Trump was not a husk of a human ruled by petty pique, he would understand the wisdom of entrapping a foe via international engagement. But because he’s so hung up on Obama, and so personally weak, he had to flex what he thinks is “strength.” His disastrous decision to tear up the nuclear deal has ramped up the dangerous tensions that presently plague us.

Stephen Walt, one of our smartest foreign affairs experts, explains it well:

“(Trump) began his campaign of so-called maximum pressure – a comprehensive program of economic warfare against Iran that sought to eliminate the country’s enrichment capacity, force Iran to change its foreign policy to suit the United States, and maybe topple the regime itself. Ordinary Iranians are suffering mightily as a result of U.S. sanctions, but the regime has neither caved to Trump’s demands nor collapsed. Instead, it has moved gradually to restart its nuclear program, cultivated closer ties with Russia and China, and retaliated against U.S. allies in the region.

“The logic of Tehran’s response is straightforward and utterly predictable: If the United States wants to make life difficult for Iran, its leaders will demonstrate that they can make life difficult for the United States too. It wouldn’t take more than a shred of strategic thinking to anticipate Iran’s response and recognize that unilateral pressure was not going to work.”

But Trump, lacking a shred of strategic thought, apparently couldn’t fathom the possibility that Iran would refuse to knuckle under, that instead it would lash out. The result is the current tit-for-tat violence that could trigger a war.

That’s why Obama’s embrace of the Corleone credo made perfect sense. Alas, Trump’s impulsive instinct is to destroy every last vestige of Obama’s work – as evidenced, most disgracefully yesterday, by his oft-repeated false accusation that Obama funded terrorism. Thanks to the “foolish” nuclear deal, he said, the Iranians “were given $150 billion…The missiles fired last night at us and our allies were paid for with the funds made available by the last administration.” (On Facebook last week, Trump was more explicit: “Obama gave them” $150 billion.)

In truth, the actual amount was reportedly closer to $50 billion and, contrary to Trump’s insinuation, it was not American taxpayer money. It was Iran’s money that had been frozen until the signing of the nuclear deal in 2013. Nor does Trump have any proof that the sums owed to Iran were specifically spent to manufacture the missiles Iran had launched. What he said yesterday, in his latest attempt to smear his predecessor’s achievement, was just the usual stew of lies and bellicosity.

I was reminded of a conversation I had in 2015 with Ami Ayalon, a former director of Israel’s domestic security service. Ayalon was visiting Philadelphia, at a time when candidate Trump was attacking Obama’s nuclear deal. Ayalon told me that Trump was being foolish: “To kill the deal is to kill American leadership in the Middle East. Their assumption that we should simply reject this deal, and that we could then go back and negotiate a better deal? This is nonsense. This can only be heard from a person who does not understand anything about Iran.”

Nor, of course, does Trump understand anything about democracy. His spinners went to Capitol Hill yesterday, ostensibly to explain why he was right to assassinate Qasem Soleimani, but mostly to tell Republican senators that they should not dissent or debate the warrior-in-chief’s decisions. Which prompted a conservative Republican senator, Utah’s Mike Lee, to blow a gasket in front of the press:

“(It) was probably the worst briefing I’ve seen at least on a military issue in the nine years I’ve served in the United States Senate. I find it insulting and I find it demeaning to the Constitution of the United States. It’s un-American. It’s unconstitutional. And it’s wrong…They are appearing before a coordinate branch of government responsible for their funding, for their confirmation, for any approval of any military action they might take. They had to leave after 75 minutes while they were in the process of telling us that we need to be good little boys and girls and not debate this in public. I find that to be absolutely insane.”

Leave it to Trump to shred every remnant of the Corleone credo. As evidenced yesterday, he can’t even keep his friends close.