It is unacceptable that Donald Trump would sabotage a route for dialogue with incendiary references to the size of his nuclear button.

The North Korean nuclear missile program poses the gravest threat to peace and security facing the world. Whether it is with a nuclear exchange or through a conventional war, the consequences of an armed confrontation would be devastating, not only for the Korean Peninsula, but for the whole world.

This is a problem for which, so far, there has not been a successful solution; dialogue and negotiation as much as pressure and sanctions have all failed. The persistent defiance of North Korea is demonstrated through the breaching of 10 United Nations Security Council resolutions over the course of the past decade. The most recent, passed on Dec. 22, imposed a hard set of sanctions on the importation of petroleum and heavy machinery as a response to the launching of a ballistic missile with intercontinental reach on Nov. 28.

Given the secrecy that envelops the activities of the North Korean regime, it is impossible to know if the outstretched hand offered by Kim Jong Un to South Korea in his New Year address should be interpreted as a sign of exhaustion, which allows a window of opportunity for negotiation, or a stratagem to divide the international community and especially the South Koreans precisely when the sanctions are succeeding.

Whatever the motivation, there is an obligation, as the South Korean government of Moon Jae-in has shown, to explore – as realistically and prudently as possible − the possibilities open for Pyongyang. What is unacceptable is that in the face of such a grave problem, President Trump sabotaged that route with incendiary references to the size of his nuclear button. His declarations show that his foreign policy only has one objective: to feed the xenophobic and racist nationalism that keeps him in power, even if that means it is necessary to make the world a more insecure place.