The escalating war of ad hominem attacks between President Trump and North Korean leader Kim Jong Un needlessly weakens the U.S. message and detracts from its policy on North Korea. Trump's personal invectives have become a distraction from the real issue of North Korea’s growing military threat and violations of UN resolutions. U.S. threats to “totally destroy North Korea,” though usually in the context of responding to an attack by Pyongyang, could hinder U.S. efforts to rally international pressure against Pyongyang.

Transforming North Korea’s defiance of the international community into a mano-a-mano duel between Trump and Kim makes the already tense situation more volatile. With Pyongyang close to achieving the ability to hit the U.S. homeland with nuclear weapons, there is also greater danger of escalation and miscalculation, making it harder for either side to step back from the brink or initiate dialogue.

Trump’s personal insults of Kim Jong Un risk goading Pyongyang into more provocative actions then it might otherwise undertake. According to a detailed CIA psychological assessment of Kim Jong Un obtained by the Los Angeles Times, Kim has a massive ego and reacts harshly and sometimes lethally to insults and perceived slights.

While Pyongyang’s propaganda missives are usually limited to blustery, even humorously over-the-top language, the regime lashes out strongly to any perceived insult of its leadership and has reacted kinetically to previous affronts to Kim. The regime conducted a cyberattack against Sony Pictures and vowed "9/11-style attacks" against U.S. movie theaters showing the movie "The Interview," which satirized Kim.

The even more direct insult issued by the U.S. president during the UN General Assembly could elicit a harsh North Korean response, such as a more provocative missile or nuclear test, an extensive cyberattack, or a tactical military attack against South Korea. Any action would risk elevating the war of words to a physical confrontation.

Kim Jong Un responded to President Trump's recent comments through a first-person communiqué, the first in North Korean history. The unprecedented declaration from the North Korean leader and other regime statements were contemptuous of President Trump and declared the North Korean leader was considering “exercising a corresponding, highest-level of hard-line countermeasure in history.”

Kim vowed to make Trump “pay dearly for his speech … face results beyond his expectation [and] tame the mentally deranged U.S. dotard with fire.” North Korean Foreign Minister Ri Yong Ho commented in New York City that Kim could be considering “the most powerful detonation of a hydrogen bomb in the Pacific.” The seriousness of Ri’s comments mean they were personally approved by Kim Jong Un.

China conducted the world’s last atmospheric nuclear test in 1980, and the United States’ final launch-to-burst test was in 1962. For North Korea to launch a nuclear warhead over heavily populated Japanese territory atop a missile that has only flown successfully a few times would be extremely provocative and dangerous.

While a nuclear airburst test remains a low probability, a North Korean ICBM test that overflies Japan is likely. Having recently reestablished the precedent for sending intermediate-range missiles over its neighbor, the next logical step for North Korea would be to demonstrate its ICBM capability by conducting a longer-range test flight far into the Pacific Ocean. After a successful Hwasong-12 IRBM launch in August, Kim Jong Un vowed to conduct "more ballistic rocket launching drills with the Pacific as a target in the future."

A long-range ICBM test would be a more direct challenge of Trump’s red line earlier this year that a North Korean ICBM test “won’t happen.” Pyongyang’s two successful ICBM test flights in July that, though demonstrating the range to hit the continental United States through a lofted trajectory, landed west of Japan. Kim and Foreign Minister Ri also disregarded Trump’s other red line that any “more threats to the United States will be met with fire and fury like the world has never seen.”

The situation on the Korean Peninsula is always on the knife’s edge of a crisis. But personifying the standoff between two leaders, each of whom has threatened to destroy the other’s country, escalates the risk of triggering a major military conflict.