President Donald Trump asked his top national security officials to build tens of thousands of new nuclear weapons during a July 20 meeting, according to an NBC News report published on Wednesday morning. The president’s request, experts say, is simultaneously impossible and terrifying.

“The insanity and folly of this … cannot be overstated,” Kingston Reif, the director for Disarmament and Threat Reduction Policy at the Arms Control Association, tweeted in response to the report. “Increasing [the US] arsenal would constitute [a] radical departure from U.S. policy and likely lead to [a] full fledged arms race with Russia and perhaps China,” he added.

There is no strategic reason for the US to increase its nuclear arsenal by such a large amount: The current US nuclear stockpile, around 4,000 nuclear devices, is more than enough to deter attacks from any hostile power. Building 32,000 more, the precise number Trump requested, would take many years and cost trillions of dollars.

And indeed, there is no indication that such a buildup is going to happen in real life. The president’s comments appear more grounded in Trump’s almost childlike fascination with military hardware — he has repeatedly requested a military parade in his honor in Washington, despite the fact that such a parade would destroy DC’s streets — than anything else.

“I do not think it is worth even analyzing this as any kind of realistic policy proposal. It is impossible,” writes Alex Wellerstein, a historian of nuclear weapons at the Stevens Institute of Technology. “It is just a sign of his lack of understanding of the issues, and perhaps a window into his own insecurities.”

Trump denied the NBC News report in a Wednesday morning tweet. “Fake @NBCNews made up a story that I wanted a ‘tenfold’ increase in our U.S. nuclear arsenal,” the president writes. “Pure fiction, made up to demean.” And, later in the day, Secretary of Defense Jim Mattis denied the report as well in an official statement.

“Recent reports that the president called for an increase in the US nuclear arsenal are absolute false,” Mattis said. “This kind of reporting is irresponsible.”

Yet NBC News’s report is was sourced to three officials who were present during the president’s remarks. NBC also reports that the July 20 meeting where Trump asked about building more nukes also precipitated Secretary of State Rex Tillerson’s now-infamous description of Trump as a “moron.”

The big question about the “moron” comment, prior to Wednesday’s report, is why Tillerson was so disgusted by the president. As Adam Mount, a senior fellow at the Federation of American Scientists puts it, “we now know why.”

Trump’s reported proposal is bonkers

According to NBC News, Trump’s comments during the July 20 briefing came after his advisers showed him a chart similar to the one above. It shows the total number of nuclear warheads in the US arsenal over time. It seems that Trump basically just pointed at the biggest number and asked for it.

“The president referenced the highest number on the chart — about 32,000 in the late 1960s — and told his team he wanted the U.S. to have that many now,” NBC News’s Courtney Kube, Kristen Welker, Carol Lee, and Savannah Guthrie write.

But there are good reasons why the US has been cutting its nuclear stockpile since the Cold War. The purpose of the US arsenal weapons is, somewhat paradoxically, not to be used. Nuclear weapons are so destructive that no one would win a full-blown nuclear war. The goal instead is to deter attacks, nuclear and nonnuclear, by other countries. And 32,000 nuclear weapons is much, much more than would be necessary to inflict devastating consequences on any attacker.

This became clear to both the US and the Soviet Union as the Cold War went on. The two biggest nuclear powers signed a series of arms control pacts designed to reduce and limit their nuclear arsenals, and thus the risk they pose to humanity’s survival. The US and Russia have since expanded on those efforts, most notably through the 2010 New Strategic Arms Reduction Treaty (or New START). The result is that the total number of nuclear weapons in existence is at the lowest point it’s been in decades:

12. The downward trend in warhead numbers is a pillar of international stability. A radical reversal of this bipartisan policy is folly. pic.twitter.com/nU9oAzk2MO — Adam Mount (@ajmount) October 11, 2017

Experts disagree on what the optimal number of nuclear weapons for the US would be. Some think it’s in the thousands, some in the hundreds, and some believe that America could secure itself without any nuclear arsenal at all. But pretty much everyone agrees that going back to Cold War levels of nuclear weapons would be absolutely absurd.

It would terrify rival nuclear powers, like Russia and China, who would quite understandably wonder what the US wanted all of those nuclear weapons for, risking a Cold War-style arms race at a time when tensions between these great powers (over issues like Ukraine and North Korea) are already high.

“Literally nobody in the military or government probably thinks that a 10X increase is feasible or a good idea,” Wellerstein writes.

It also isn’t clear how the US would even go about building all the new nuclear weapons that Trump requested.

Cheryl Rofer, a scientist who studies nuclear policy, explains that the US only has one facility that can “manufacture the fissile parts of nuclear weapons”: Los Alamos National Lab in New Mexico. Los Alamos, per Rofer, “can maybe produce 80 a year.” It would take Los Alamos at least 350 years to put together the stuff necessary to fill Trump’s request.

The cost of building new facilities like Los Alamos is, in her estimation, in the trillions. and that’s just for one part of the construction of a working nuclear weapon (you also have to assemble a working nuclear device, put them inside warheads or bombs, and so on).

So Trump’s proposal during the meeting would be not only destabilizing and prohibitively expensive but also likely impossible to accomplish within the next few centuries. And it seemed founded solely in Trump’s desire to have as many nukes as presidents before him.

“Trump's reason for wanting more nuclear weapons — he doesn't want to be at the bottom of the curve — is, well, ‘moronic,’” writes Jeffrey Lewis, a nuclear expert at the Middlebury Institute of International Studies.

No wonder the military apparently didn’t take it very seriously.

Trump and weapons

The president has long been fascinated by nuclear weapons. This fascination has at times manifested as horror at their destructive power, at times as a desire to build more of them — but, above all, has rested on a foundation of ignorance.

In a December 2015 Republican debate, moderator Hugh Hewitt asked Trump about the “nuclear triad” — America’s three-part system for delivering nuclear weapons (bombers, submarines, and intercontinental ballistic missiles). Trump’s answer was confusing:

We have to be extremely vigilant and extremely careful when it comes to nuclear. Nuclear changes the whole ballgame. ... The biggest problem we have is nuclear — nuclear proliferation and having some maniac, having some madman go out and get a nuclear weapon. That's in my opinion, that is the single biggest problem that our country faces right now.

There are two interesting things about this. First, Trump suggests that he sees large global nuclear stockpiles as a problem. Second, he doesn't appear to know any of the major policy questions surrounding the nuclear triad, or even what the nuclear triad is.

That became especially clear when Hewitt followed up, pressing Trump to answer the actual question about the triad. Trump’s response? “I think — I think, for me, nuclear is just the power, the devastation is very important to me."

This pattern — an abstract abhorrence of nuclear weapons paired with seemingly confused views on actual nuclear policy — continued throughout the campaign. In a March 2016 town hall, for example, host Chris Matthews pressed Trump on whether he’d use nuclear weapons. He seemed to say both no and yes at the same time, saying he’d be “the last one to use nuclear weapons,” but also that he would be very willing to nuke ISIS territory in response to a terrorist attack:

TRUMP: I’d be the last one to use the nuclear weapons, because that’s sort of like the end of the ballgame. MATTHEWS: So, can you take it off the table now? Can you tell the Middle East we are not using the nuclear weapon on anybody? TRUMP: I would never say that. I would never take any of my cards off the table... MATTHEWS: Where would we drop — where would we drop a nuclear weapon in the Middle East? TRUMP: Let me explain. Let me explain. Somebody hits us within ISIS — you wouldn’t fight back with a nuke?

In August 2016, MSNBC host Joe Scarborough recounted a story an unnamed foreign policy expert told him about Trump and nukes. In it, Trump expresses confusion as to why the US doesn’t use its nukes.

"Several months ago, a foreign policy expert on the international level went to advise Donald Trump. And three times [Trump] asked about the use of nuclear weapons. Three times he asked at one point if we had them why can't we use them," Scarborough said.

This continued after Trump won the election. In December, Trump tweeted that the US “must greatly strengthen and expand its nuclear capability until such time as the world comes to its senses regarding nukes.” When MSNBC’s Mika Brzezinski asked him about the possibility of this policy setting off an arms race with Russia (which is also talking about expanding/modernizing its nuclear arsenal), Trump’s answer was simple: “Let it be an arms race.”

And in February, President Trump interrupted a phone call with Vladimir Putin to ask an aide what the New START agreement was, as he apparently was not aware of the landmark arms control agreement or how it worked. Once he heard the basics, he immediately informed Putin that he was against it.

The point, then, is that Trump’s comments in the July 20 meeting are very much in line with his longstanding way of talking and thinking about these weapons. He believes nukes are bad but seems far more willing to build more of them — and even think about using them — than any prior president.

Nuclear weapons, for him, seem less like a real destructive force that he needs to study carefully and understand, and more like a toy he gets to play around with now that he’s running a country. If anything should terrify us about the Trump presidency, it should be that.