Jon B. Wolfsthal

Opinion contributor

America’s top priority must be to avoid a second Korean war. Yet such a war is closer than ever and appears almost inevitable unless America changes the approach President Trump has been using since he took office. The greatest risk of war with North Korea is not sudden action by Kim Jong Un, but Kim responding to a perceived attack by Trump. North Korea foreign minister Ri Yong-ho drove that home Monday when he called Trump’s threats against his country “a clear declaration of war.”

The United States has been in a technical state of war with North Korea since the end of the Korean War in 1953. Every president since Dwight D. Eisenhower has had to navigate the risk of conflict with North Korea. What’s new is Trump’s bombastic approach to this long-standing challenge — his personal insults, crazy tweets and threat at the United Nations to "totally destroy North Korea."

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Kim knows North Korea cannot win a war with the United States and that his only hope of survival is to strike fast and hard to stop a conflict before it gets going and he starts to lose. This is the strategy that led North Korea to deploy thousands of long-range artillery pieces near Seoul, and that is the thinking behind its nuclear program. Hit hard, hit first, seek a truce.

The unprecedented, increasingly bizarre name-calling — “Rocket Man” and “madman” from Trump, met by “dotard” from Kim — make this fragile situation even more dangerous. Trump’s aggressive statements are unlikely to convince North Korea to abandon its nuclear program, nor are stepped-up military activities in and around Korea. Kim may only cling to it more tightly. Watching what happened to Iraq, Libya and even Ukraine, he has apparently decided nuclear weapons are only way to secure his power and the future of his country.

When Trump said in April that an armada was steaming toward the North, Pyongyang had no idea what he meant and no way to determine if it was true or not. Trump’s statement last weekend that the days of the North Korean leader were numbered further increased North Korea’s sense that an attack is either imminent or more likely than it was in the past.

How will North Korea's leaders respond to such statements? Even they don’t know, but relinquishing their nuclear insurance policy seems pretty low on the list of possibilities. Threats make poor nonproliferation strategy. That did not work when the United States threatened the Soviet Union or China, just as it failed when India threatened Pakistan.

What we need is a clear approach to prevent war and de-escalate tensions between the United States and North Korea.

The president and his advisers need to do everything they can to ensure that the United States and South Korea can repel a North Korean attack, and at the same time they must avoid statements that increase the chance North Korea will misinterpret these steps as a prelude to an attack.

We must also open a direct line of military to military communication with North Korea. The greatest risk of war now is the unanticipated event that neither the United States nor North Korea can control. A plane crash or naval collision at the wrong time, a cyber attack by some unnamed group targeting either country in a time of tension, the lone soldier who snaps — any of these could be the spark that sets the peninsula on fire. And we have no reliable way to let each other know any of them were accidents or not directed by the other side.

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No red phone or computer link exists with North Korea. The only regular means of communication between the two countries right now is a soldier with a bullhorn shouting across the demilitarized zone that has separated North and South Korea since the 1950s. Tweeting 140 characters at a time is no substitute for direct talks, especially among adversaries.

Bilateral military-to-military talks are needed, but even talks between the two organized by the Chinese military leadership would be stabilizing. Senior American military officials, including the Chairman of the Joint Chiefs General Joe Dunford, talk regularly with every country on earth with nuclear weapons except North Korea — the one we are most likely to end up fighting. That makes no sense.

These steps would reduce the risk of unintended conflict and make America and our allies safer. Nothing along these lines would require us to accept North Korea as a nuclear weapon state, or reduce the security of our allies in South Korea or Japan. It would require the president to listen to his top military advisors who understand the risks of escalation all too well and have urged him to avoid inflammatory statements. The risks of an unintentional and sudden war are too great for us to continue on our current path.

Jon B. Wolfsthal, former senior director for arms control and nonproliferation at the National Security Council, is director of the Nuclear Crisis Group and senior adviser to Global Zero. Follow him on Twitter: @JBWolfsthal.