*The only real hope of getting North Korea to relinquish its nuclear weapons is to apply such significant economic pressure that the regime is forced to make a choice between economic collapse and the verifiable dismantling of its nuclear weapons and facilities. Such pressure would need to be accompanied by an offer of full political and economic normalization if Pyongyang agreed to abandon its nuclear program. The only country capable of applying such pressure is China.
* the US would guarantee to help handle any North Korean refugee problem
* the US would guarantee no troops would cross the 38th parallel except for temporary
Evacuating U.S. forces from South Korea would allow American foreign policy makers wider latitude in dealing with North Korea. For instance, the U.S. could issue an ultimatum to the North Korean regime to dismantle its clandestine nuclear weapons program or else face the consequences, which might include an attack on North Korean nuclear facilities, a naval blockade, or an attack on North Korean leadership. These actions would be entirely within the right of America to defend itself from a regime that continues to threaten U.S. national security. But, so long as America remains tied at the hip with South Korea, none of these more effective steps will be taken.