SEOUL, South Korea — President Barack Obama landed here shortly after dawn today for a three-day visit during which he will promote efforts to secure the world's nuclear stockpiles, and where he got a firsthand look at one of the world's most secretive nuclear states, North Korea.
Five hours after landing at Osan Air Force Base, south of Seoul, Obama traveled to the demilitarized zone between North and South Korea, where he greeted some of the 28,500 U.S. troops stationed in South Korea.
He visited Observation Post Ouellette, a hilltop border post ringed with sandbags, overlooking the heavily fortified, brown hills of the North Korean countryside.
While touring the demilitarized zone is a time-honored stop for a U.S. president, Obama's visit — his first — comes amid a sudden spike in tensions after North Korea announced plans to launch a satellite, atop a long-range missile, next month to honor the 100th anniversary of the birth of its revered founder, Kim Il Sung.
The United States has condemned the plans as a violation of the North's international obligations, and has warned that a satellite launching would breach a recent agreement to supply North Korea with desperately needed food aid in return for preliminary talks over its nuclear program.
The timing of Obama's visit is also symbolic, coming a day before the second anniversary of the sinking of a South Korean Navy warship, the Cheonan. An international investigation concluded that the ship was torpedoed by the North, though the North Koreans deny culpability.
Administration officials said traveling to the demilitarized zone, where U.S. troops serve alongside South Korean troops, would give Obama a chance to honor the crew of Cheonan and signal the close bonds between South Korea and the United States.
On Sunday afternoon, Obama will travel back to Seoul to meet South Korea's president, Lee Myung Bak, who is playing host to more than 50 world leaders at a nuclear security summit meeting.
In 2009, Obama proposed the idea of a biannual global meeting to discuss ways to prevent nuclear material from falling into the hands of terrorists.
Before a joint news conference and dinner with Lee, the president will meet with Prime Minister Recep Tayyip Erdogan of Turkey to discuss the escalating violence in Syria, as well as the security situation in Iraq after the withdrawal of the last U.S. troops.