This treaty between the U.S. and Japan was signed on January 19, 1960. It strengthened the U.S. and Japan's commitments to each other, including military cooperation.

In a series of Northeast Asian summits, China gave no signal it was prepared to ramp up pressure on North Korea, to the detriment of regional security efforts, writes CFR's Sheila Smith.

Paul B. Stares argues that the World Cup offers an unparalleled stage for shaming and further isolating North Korea in response to its sinking of a South Korean naval vessel.

Richard N. Haass says the United States can send a message to North Korea by signing the Korea-U.S. Free Trade Agreement.

North Korea's alleged sinking of a South Korean ship could have been part of a legitimization process to prepare for a new leader to succeed the ailing Kim Jong-Il, says North Korea expert Victor Cha.

The United States, South Korea, and Japan have displayed solidarity in response to ramped-up tensions with North Korea, but China needs to be more active in crisis diplomacy, says CFR's Sheila Smith.

South Korea's charge that North Korea caused the sinking of one of its warships is likely to result in a drawn-out effort to get the UN Security Council to censure Pyongyang, writes CFR's Scott Snyder.

Carolyn M. Leddy says, "The flap over an airbase in Okinawa points to larger problems in the U.S.-Japan security alliance."

Absent evidence of N. Korea's involvement, S. Korea's response to the recent sinking of one of its ships has been measured. But public anger about the incident will impact June elections and increase scrutiny of the defense ministry, says CFR Korea expert Scott Snyder.

Carolyn M. Leddy says, "the time is long overdue for Japan to start acting like it understands the essential role for Tokyo in maintaining peace and stability in East Asia and throughout the world."

Sheila A. Smith says that Japan must go beyond its commitment to reduce its own nuclear weapons and play a more active global role in persuading others to abandon their use.

A South Korean security expert says it is likely that North Korea will ratchet up pressure over the summer through threats and possible missile tests if Washington refuses to engage Pyongyang in direct talks.

Sheila A. Smith says the nuclear summit offers Japan the opportunity to voice its long held aspirations for a nuclear free world.

Marcus Noland outlines two recent surveys of North Korean refugees in China and South Korea which found, not surprisingly, that North Koreans privately hold highly critical views of the regime and are rather miserable.

An incident involving a sunken South Korean naval vessel has highlighted the ongoing tensions with North Korea and ongoing potential for naval confrontations between the two sides, says CFR's Scott Snyder.