HARI SREENIVASAN:

North Korean dictator Kim Jong Un recently said his goal is to reach an "equilibrium of real force" with the United States and dissuade talk of U.S. military action against his regime. And that he wants to finish his nuclear weapons program despite sanctions.

Kim's comment comes after North Korea test-fired a ballistic missile over northern Japan for the second time.

North Korea's state-run media released this video, which shows the missile launch along with these photos of Kim watching it.

The North Korean threat — and China's assertiveness in the South China Sea — underscore how Japan still relies on the U.S. military for protection, just as it has since the end of World War II.

Earlier this month, Defense Secretary Jim Mattis said the U.S. will work with Japan to enhance its missile defenses, and the U.S. commitment to defend Japan remains, quote, "ironclad."

In tonight's Signature Segment, NewsHour Weekend Special Correspondent Amy Guttman reports from the Japanese island of Okinawa on how U.S. bases there are a cause of concern to many residents.