In April 13, 2012, North Korea launched a long-range ballistic missile, but it exploded over the Backryoung Island. North Korea launched the missile to celebrate the completion of “the great and prosperous state” and the establishment of Kim Jong-un regime on the occasion of “the dear leader” Kim Il Sung’s 100th birthday. The North Korean purpose was not fulfilled due to the failed missile launch. The missile launch was a violation of the U.S.-North Korea agreement which was announced on February 29, 2012. The agreement stipulated that North Korea would stop uranium enrichment program and suspend long-range missile launch, while the United States agreed to provide 240,000 tons of nutritional support. North Korea must have reasons to insist on the launch even under very strong international pressures to stop the launch. The fourth North Korean Worker’s Party Representatives Meeting, which was held on April 11, 2012, had Kim Jong-un as the first secretary of the KWP and the chairman of the KWP’s Central Military Committee. On April 13, 2012, the Supreme People’s Assembly had also Kim Jong-un as the first chairman of the Defense Committee, the most powerful organ in North Korea. Thus, Kim Jong-un looked as if he finalized hereditary succession of three generations. After Kim Jong-il’s sudden death in December 2012, Kim Jong-un has been heavily dependent upon his families and the second and the third generation revolutionaries to stabilize his regime. He will follow the military-first politics, maintain closed political system, develop nuclear weapons and ballistic missiles, and continue to provoke against the South, as his father did. In order to save North Korea from the crises, Kim Jong-un must give up the nuclear and the ballistic missile programs and pursue reform and opening its political system. Nevertheless, he will be reluctant to do so, because he worries that North Korea may collapse if it changes Kim Jong-il’s policy line. South Korea must have deterrent power against North Korean conventional forces on the one hand, and make continuous and strenuous efforts to reform and open North Korean political and economic system. That will be best for peace and stability in the Korean peninsula and for the ultimate unification of the peninsula.