So President Donald Trump warns, amid reports North Korea, in its zeal to build an intercontinental ballistic missile to hit our West Coast, may test another atom bomb.

China shares a border with North Korea. We do not.

Why then is this our problem to "solve"? And why is North Korea building a rocket that can cross the Pacific and strike Seattle or Los Angeles?

Is Kim Jong Un mad?

No. He is targeting us because we have 28,500 troops on his border. If U.S. air, naval, missile and ground forces were not in and around Korea, and if we were not treaty-bound to fight alongside South Korea, there would be no reason for Kim to build rockets to threaten a distant superpower that could reduce his hermit kingdom to ashes.

While immensely beneficial to Seoul, is this U.S. guarantee to fight Korean War II, 64 years after the first wise? Russia, China and Japan retain the freedom to decide whether and how to react, should war break out. Why do we not?