We are running a terribly unwise experiment: What happens when you replace U.S. presidential leadership with the slapstick antics of a clown?

On Saturday, President Trump issued the following statement: “Why would Kim Jong Un insult me by calling me ‘old,’ when I would NEVER call him ‘short and fat?’ Oh well, I try so hard to be his friend — and maybe someday that will happen!”

There is a natural tendency to become inured to Trump’s gushing stream of nonsense. Resist the urge. Read that statement again. The president of the United States, in the midst of a trip to Asia, taunted the nuclear-armed dictator of North Korea in a manner most sixth-graders would consider juvenile.

There was a time when the world looked to the U.S. president to speak clearly in defense of freedom, democracy, the rule of law and respect for human rights. I refer to the entirety of modern U.S. history before January, when Trump assumed the high office he now dishonors.

His Asia tour has been at times a disaster, at times a farce. What was the most shameful moment? Perhaps when he announced that he has a “great relationship” with Philippine President Rodrigo Duterte, who has encouraged police and vigilantes to fight the trade in illegal drugs by assassinating suspected traffickers without the bother of arrests or trials. At least 7,000 and perhaps as many as 13,000 people have been slain.

The White House claimed that human rights came up “briefly” in a private meeting between the two leaders, but Duterte said it didn’t come up at all. In fact, during a gala dinner, the buffoonish Duterte serenaded Trump with a Philippine ballad that includes the lyric, “You are the love I’ve been waiting for.”

The spectacle was simply appalling. One might argue, however, that Trump’s kowtowing to Russian President Vladimir Putin was even worse.

The U.S. intelligence community has concluded that the Russian government directed a multipronged campaign to meddle in the 2016 election, with the aim of helping Trump win. Putin denies having committed this hostile act, and Trump, for some reason, takes the former KGB officer at his word.

“He said he didn’t meddle. I asked him again. You can only ask so many times,” Trump told reporters on Air Force One, flying over Vietnam from Danang to Hanoi. “Every time he sees me, he says, ‘I didn’t do that.’ And I believe, I really believe, that when he tells me that, he means it.”

Putin’s office claimed that Trump didn’t raise the issue at all. It is astounding that we have to wonder whether the White House or the Kremlin is telling the truth.

Unbelievably, Trump described former U.S. officials who say Putin is lying — fired FBI director James B. Comey, former CIA director John Brennan and former director of National Intelligence James R. Clapper Jr. — as “political hacks.” Trump later said grudgingly that he has confidence in U.S. intelligence agencies “as currently constituted” — now that they are led by Trump appointees.

Someday we will learn why Trump, usually so full of bluster, becomes as deferential as a puppy dog whenever he’s around Putin. Maybe special counsel Robert S. Mueller III will provide the answer.

It is reasonable to assume that all the governments whose leaders Trump encountered during the trip have consulted psychologists for advice on how to push Trump’s buttons. The host nations all came up with the same answer: pomp and circumstance.

“It was red carpet like nobody, I think, has probably ever seen,” Trump said — ridiculously — of the overall welcome he received. And yes, there were red carpets everywhere. And glittering banquets. And opportunities to review the troops.

Chinese President Xi Jinping laid it on thickest, personally taking Trump and the first lady on a tour of the Forbidden City and hosting a state dinner — Trump called it “state-plus-plus” — in the cavernous Great Hall of the People. Xi clearly understands how much Trump loves flattery and ceremony, as opposed to substance.

Meanwhile, as Trump incomprehensibly pursues a policy of “America first” neo-isolationism — refusing even to adequately staff the U.S. diplomatic corps — China moves globally to fill the vacuum. Japan and South Korea wonder whether the U.S. nuclear umbrella still protects them. And the nations Trump abandoned when he nixed the Trans-Pacific Partnership have moved forward to form a trade pact of their own — without us.

This is what happens when a very big nation is led by a very small man.