All that sweet talk Donald J. Trump has been heaping on Kim Jong Un of late seems to have gone into one ear and out the other.

The North Korean dictator seems to be putting the planned Trump-Kim summit in some jeopardy because he’s angry over the planned joint military exercises that will take place with South Korean and American troops.

Kim thinks the military maneuvers are meant to prepare for an invasion of North Korea, or so he says. Thus, the summit might not happen if Kim decides to pull the plug on it.

What is happening here?

U.S. and South Korean troops have been practicing for years since the ceasefire ended shooting during the Korean War. We haven’t invaded the North yet. The exercises are meant to prepare the South for a possible invasion from the North; I mean, the North did invade the South in 1950, which caused the Korean War. Kim Jong Un’s grandfather started the fight.

The president of the United States was yammering about “little Rocket Man,” and bragging about the size of his “nuclear button.” He was taunting Kim to try anything at all to provoke a response that would deliver “fire and fury the likes of which the world has never seen.”

Donald Trump changed secretaries of state. The new guy at State, Mike Pompeo, went to North Korea in secret and then the nations announced the summit between Trump and Kim.

Suddenly, Kim has become a paragon of virtue in Trump’s mind. He released those three Americans he held captive. Trump hailed Kim Jong Un as a fine man, a wonderful fellow.

Now we have Kim threatening to upset everything all over again.

Don’t tell me the North Korean despot responses positively only to epithets. That cannot possibly be true, can it?

My hope is that Trump holds his fire. If he’s able.

International statecraft is a nuanced endeavor, but it’s not an entirely complicated matter.

The best practitioners of it look forward and don’t bother looking back, let alone tossing stones at those who came before them in the high office they occupy.

Thus, Donald Trump’s statements today about the pending peace agreement between South and North Korea lacked a sense of nobility one might expect from the president of the United States.

Trump spoke to the media along with German Chancellor Angela Merkel. He spoke seriously about the handshake and the historic meeting that occurred overnight between North Korea’s Kim Jong Un and South Korea’s Moon Jae-in. The two men have agreed to strike a peace deal on the Korean Peninsula, ending the official state of war that has existed since the Korean War hostilities ended in 1953.

Then he did that thing that annoys the living daylights out of me. He kept referring to his presidential predecessors’ “mistakes” in dealing with the reclusive North Korean regime.

Holy crap, Mr. President! Enough, already!

I expect fully for Trump take full credit for the deal that awaits the two Koreas. That’s fine. He can take credit if he wishes. But the expected deal came together through a complicated network of international relationships.

I just want the president to look forward from here. Kim Jong Un and Moon Jae-in have taken a huge step toward a long-sought-after peace agreement. It was forged by the deaths of hundreds of thousands of men — roughly 50,000 of whom were Americans — who fought a war that ended in a stalemate.

There is no need — none at all — for the president to re-litigate how his predecessors sought in vain to achieve the noble goal of peace in Korea.

I awoke this morning to an absolute stunner of an announcement.

Kim Jong Un and Moon Jae-in — the presidents of North and South Korea, respectively — have agreed to actually end the Korean War.

End the war? Yes. The Korean War never officially ended with a peace treaty. They stopped the shooting in 1953 after an armistice was signed, ending three years of bloody conflict on the Korean Peninsula.

The Koreas has been functioning with a cease-fire in place. The Demilitarized Zone separating the countries is nothing of the kind: it is the most militarized piece of real estate on Earth.

So, where do we go from here?

Kim and Moon signed an agreement to end the war. The treaty signing will occur later this year, according to the document the men signed.

But there’s more. There now appears some serious movement toward discussions relating to the denuclearization of the peninsula. That’s right. Kim Jong Un has agreed, apparently, to enter serious talks to take down his country’s nuclear ambitions.

Now for a big question: Who gets the credit for this seemingly monumental event? I have a strong hunch that the president of the United States, Donald J. Trump, is going to claim all the credit for himself. He is likely to tell us his tough talk regarding “Little Rocket Man” has brought Kim to his senses.

Well, the president deserves some credit. He needs to share it with the People’s Republic of China, which quite likely also has persuaded Kim to end this ongoing conflict. North Korea has precisely one dependable ally on Earth. It is the PRC. Does anyone believe that Kim would do anything so significant without China signing off?

I am stunned today to hear the news that came out of Korea.

Let us all say a prayer that Kim Jong Un — who is as mercurial and unpredictable as Donald Trump — remains faithful to the signature he has affixed on a document pledging to end the Korean War.

Sixty-five years after the end of the bloodshed, it’s about time!

I must have missed something.

South Korea has been arguably our staunchest ally in East Asia since, oh, the Korean War of 1950-53. We fought side by side with the South Koreans against North Korea and later, the People’s Republic of China.

Now the North has nuclear bombs. It is threatening to use them against South Korea. The United States is supposed to stand ready to defend the South against the North.

So, why is Donald J. Trump browbeating South Korea into doing more to deter North Korea from threatening to toss the rest of the world into a nuclear war?

South Korean leaders say they want to “talk” with their neighbors in the North. The U.S. president is having none of it. He has taken to Twitter to suggest that South Korea is run by a government of “appeasers.”

Appeasers? Are you kidding me?

No country on Earth is feeling more nervous about North Korean dictator Kim Jong Un’s crazy threats than South Korea. That’s not good enough for Trump, who’s also now threatening to terminate a U.S.-South Korea trade agreement.

Uh, Mr. President, these guys are on our side. They’ve got more to lose in a military confrontation with North Korea than anyone.

South Korean President Moon Jae-in got elected this year promising to “talk” to North Korea. He fired back at Trump, saying that South Korea “cannot tolerate another catastrophic war on this peninsula.”

Do you think?

Why in the world cannot the president of the United States treat the South Koreans like the valuable ally they’ve been — and need to continue to be as we try to work our way through this crisis with the North?

Talk of “appeasers” and threats to cut off trade won’t do the job.