Donald Trump isn’t on trial for paying off Stormy Daniels. He’s on trial for being stupid.

I’m sorry if I’m going to offend Donald Trump’s supporters here, but I have to play it as it lays.

Even if we call Trump’s hush-money case a political show trial, one unavoidable fact still remains: If the facts of the case as alleged are substantially true, and Trump paid off Stormy Daniels as described, the former president is only facing this situation at all because of his own monumental stupidity. That’s it.

Set aside all the ethical issues for a moment. What kind of an idiot makes an illicit payment through the banking system, leaving a digital trail as clear as day?

Especially someone who knows he is also charging into a political storm by running for president in the most tendentious, controversial way possible?

Maybe he figured it wouldn’t matter, because when he allegedly made the payments, in late October 2016, he thought he was going to lose the presidential election anyway. Who knows?

Trump denies the charges and has pleaded not guilty. The trial starts Monday.

Read more: Inside the secret meeting where Donald Trump’s ‘catch and kill’ trial began

But according to Manhattan District Attorney Alvin Bragg, a Democrat, in October 2016 Trump and his fixer Michael Cohen paid off porn star Daniels for her silence through an elaborate funding scheme. Bragg says Cohen set up a shell company, and then used that to funnel money from his own bank account to Daniels’ attorney’s bank account. Then, says Bragg, after the election Trump paid back Cohen through a series of monthly checks. Eleven of them.

Each was supposedly to pay Cohen for unspecified legal services. Bragg says there was no retainer.

Bragg says Trump and Cohen “also took steps that mischaracterized, for tax purposes, the true nature of the payments” (my italics).

If that latter part is true, it would be a level of stupidity, and cheapness, that simply defies belief.

As a Mafia boss supposedly said of Richard Nixon during the Watergate scandal: What kind of dolt bugs his own office?

Cohen has already pleaded guilty and served time. These are still only accusations and Trump has yet to make his defense in court.

You don’t have to be a Trump voter to question the merits of this case, especially during an election campaign. Many non-Trumpers, and even anti-Trumpers, have serious doubts about it as well. (They also note that cases such as this one have been helping Trump politically for the past year.)

On the other hand, you don’t have to be a liberal, or a Trump critic, to think that if the facts of the case are pretty much as Bragg has presented them, the entire alleged scheme to pay off Daniels was monumentally stupid from start to finish.

Trump should have paid heed to the wise words of the late comedian Jimmy Durante, who used to joke to illicit lovers: “Say with roses, and say it with mink — but never, ever, say it in ink.”

In other words, never put something in black and white if you want it to stay private.

A friend in politics refuses to say anything in an online message, even a text message or via WhatsApp, that he wouldn’t want to see on Page Six of the New York Post. “There is no longer any such thing as privacy,” he tells me.

Here’s the crowning idiocy of this case: The easiest way to keep an illicit payment secret these days is to make it with gold coins, such as South African Krugerrands or the American Eagles issued by the U.S. Mint.

And the easiest place in America to buy them is on 47th Street in Midtown Manhattan. Ten blocks from…er…Trump Tower. The residence of one Donald J. Trump.

Can’t he read a map?

The government makes it almost impossible to pay for things with large amounts of cash. But large amounts of gold? No problem.

Back in 2016, at the time of the alleged Daniels payoff, gold was trading at around $1,300 an ounce. (It’s now $2,340.) So if Trump wanted to pay Daniels $130,000, all he needed was 100 U.S. Eagles.

Total weight: Just under 7 pounds. That’s the same as maybe two laptops. We are not talking about a truck with an armed guard.

Trump didn’t even have to buy the coins with cash. It’s easier to buy them with a check or wire transfer. The key point is that once you have the coins, the digital trail goes cold. There is no way for Bragg, or anyone else, to prove what happens to them or where they end up.

The only “fingerprints” are literal fingerprints. If you handle the coins using gloves, you don’t even leave those.

I wrote about this a year ago. The longer this case has gone on, the more incredulous I have become that someone would be so stupid as to leave such a simple and obvious money trail.

Some elaborate conspiracy theorists might even try to argue it was deliberate, to provoke just this kind of court case. (I know the conspiracy theory has yet to be invented that can’t find believers in our country, but this would be a stretch.) Still, the Bragg indictment just over a year ago electrified the election race and boosted Trump’s chances of winning the nomination and the White House.

(Obviously, I’m deliberately avoiding making any comments about either the ethics of having an affair with Daniels or of paying her off. I’ll leave those comments to others).

If Donald Trump and Michael Cohen really did pay off Stormy Daniels, what a shame they never subscribed to MarketWatch. If they had, they’d have read this article we ran in April 2016 — a full six months before the alleged Daniels payment.

(They might also have read this one, that we ran a full year before the alleged Daniels payment.)

Armed with this wisdom, they’d have gone down to 47th Street and loaded up on gold coins. No one would ever have heard about the Daniels payment, Cohen would never have gone to jail, and Donald Trump would not now be on trial in New York.