President Trump and his national security team should do all they can to dissuade President Moon Jae-in of South Korea from cancelling joint military exercises. The South Korea leader wants exercises to be suspended until after February 2018's Winter Olympics.

Speaking to NBC News on Wednesday, Moon said, "It is possible for South Korea and the U.S. to review the possibility of postponing the drill, I have made such suggestion to the U.S., and the U.S is currently reviewing."

Moon is making a mistake.

For a start, North Korea has shown no inclination to view appeasement as anything other than a sign of weakness. Indeed, the present condition of threat vis-a-vis North Korea is reflective of the decade-long failure of South Korea's "sunshine policy" towards Kim Jong Un's father, Kim Jong Il. That policy inculcated North Korean officials with the belief that extortion pays off.

As problematic is the fact that Moon's comments takes place alongside an increasingly fragmented U.S. stance toward North Korea. Consider the inopportune words offered by Secretary of State Rex Tillerson, in which Tillerson diluted the Trump administration's pressure stance towards Kim Jong Un. For North Korea and its Chinese patron, the fragmentation suggests America is panicking and growing malleable.

This makes U.S. threats against North Korea seem less credible and it weakens necessary efforts to get China to increase its pressure on Kim. Moon's words will also inspire China to believe that Seoul can be separated from Trump.

Yet there's a more basic rationale for why cancelling military exercises is a bad idea. Put simply, it weakens the U.S. and South Korean military ability to effectively prepare for a new conflict on the peninsula. After all, while there is a deterrent-messaging element to military exercises, they also employ significant training principles and sharpen the prospective lethality of allied forces. Be under no illusions, that lethality will be crucial to winning in short order and with as few casualties as possible.

I have one final thought here: For an array of tactical and strategic reasons, South Korea should be able to secure the Olympics. Bowing to Kim is thus both unnecessary and unhelpful.