South Korea Koreas US Military Drills

FILE - In this March 30, 2015, file photo, South Korean Marines march after landing on the beach during the U.S.-South Korea joint landing military exercises as a part of the annual joint military exercise Foal Eagle between South Korea and the United States in Pohang, South Korea. AP Photo/Lee Jin-man, File)

Despite his walk-out from the recent summit meeting in Hanoi with North Korea’s dictator Kim Jong Un, President Donald Trump’s welcome effort to persuade North Korea to abandon nuclear weapons does not appear to be dead.

The enormous, complex task certainly is worth pursuing. In December 2016, President Barack Obama informed President-elect Trump that North Korea, on which he had deferred action for several years, was now the most important foreign policy and national security issue facing the nation, as the Wall Street Journal reported at the time.

Mr. Trump’s approach to this issue, invoking close consultation with China, aggressive counter-threats, harsh sanctions, personal involvement, a glittering promise of prosperity for a non-nuclear North Korea and his own special brand of unctuous diplomacy, has been highly unorthodox. But it has reduced the immediate threat and continues to hold out the possibility that it could succeed where previous traditional attempts have failed.

There are good reasons to think North Korea will make a new offer in its attempt to ease U.S. sanctions. High among them is the hope Mr. Kim himself has raised among North Koreans that normalization of relations with the United States will succeed in greatly improving their living standards.

Pyongyang’s anxiety to move ahead was made evident when Mr. Kim’s foreign minister protested against Mr. Trump’s statement that North Korea wanted all sanctions lifted in exchange for its offer to verifiably shut down the only known facility it has, at Yongbyon, for making nuclear weapons-grade explosivesfrom plutonium.

Only a partial lifting of sanctions was requested, he said.

But accepting that offer could have evolved into negotiations over which sanctions would be removed for closing a facility North Korea says it does not need.

The United States has bought this horse several times already, as a review of negotiations between Pyongyang and Presidents Bill Clinton, George W. Bush and Obama clearly shows.

North Korea placed Yongbyon under international inspection from 1994 to 2002 — when the Bush administration discovered a secret uranium enrichment operation — and from 2007 to 2009, each time receiving economic help. It was again closed from 2012 to 2015 during negotiations with the Obama administration before being reopened with improvements.

The deal offered to Mr. Trump also would have left North Korea in firm possession of an arsenal of short- and medium-range missiles, 30 to 60 nuclear warheads and 28 primitive slow-to-set-up ICBMs stored in caves on transporter vehicles, as a threat to the United States, according to public estimates.

A far more serious threat would have been posed by ready-to-fire solid-fuel missiles. But as part of the current no-testing detente North Korea stopped testing such missiles well before it could develop a solid-fuel ICBM.

The proffered deal would also have left uncertain whether North Korea has other, hidden facilities for processing fissionable materials to make more nuclear warheads.

And it could have greatly eased the economic pressure on North Korea, which has forced odious economic sacrifices on its people to become a nuclear power.

Mr. Trump was right to say no, and to demand verifiable full denuclearization as the price for removing sanctions.

The fact the North Korea is still ready to talk is a sign that it might be ready to actually give up nuclear weapons. As President Trump has said, time will tell.

Instead of grousing about the president’s continued flattery of the repellent Mr. Kim, a ruthless ruler who reputedly had his own half-brother killed, Americans should be glad Mr. Trump is spending so much time and personal effort trying to bring North Korea into the civilized world without nuclear weapons. His predecessors tried and failed, but none of them made as much effort as Mr. Trump, or held out such glittering rewards to the other side.