The primary reason isn’t about Trump himself, but the incredible restraint and caution of South Korea, which is unlikely to change. U.S. allies in Seoul have accepted incredible provocation from the North Korean government but have avoided war. In the 1960s, when North Korea concluded that it could not foment enough domestic dissent in the South to destroy the rival government, it attempted an assassination of South Korea’s president. In 1987, a North Korean spy blew up a South Korean airplane in an attempt to destabilize the South Korean government ahead of the Seoul Olympics. Seoul has long shown remarkable resolve in avoiding a wider conflict with its neighbor.

This strategy of keeping peace even at a high cost has some long-term risks, but South Koreans have benefited from it for decades. Even if a U.S. president is feeling emboldened against North Korea’s regime, he is unlikely to get approval and support from South Korea for doing so. And no one will advise the president to do something in the Korean peninsula against the wishes of an ally that otherwise shares some of the costs and burdens of U.S. policy.

In fact, no player in the region wants to see a major change from the status quo, even if it means putting up with obnoxious and provocative weapons tests, and hysterical rhetoric from the regime in Pyongyang. After all, the internal collapse of the North Korean government is the biggest danger to the region. Refugees from North Korea could quickly overwhelm South Korean society’s ability to assimilate them. And the amount of disorder could quickly cause China to take a larger leading role in creating and maintaining a transitional government in Pyongyang. No one wants this.