The warming relations on the Korean Peninsula appear to have reached a new high point, but looks can be deceiving. On March 5, North Korean leader Kim Jong Un met with a 10-member South Korean presidential delegation -- the first such meeting during his seven-year tenure. The delegation's main goal is to open dialogue between the United States and North Korea. But with the United States sticking to demands for denuclearization and North Korea intent on the opposite, such a dialogue (if it happens) will quickly run into a wall of non-negotiable issues....