SEOUL, South Korea — Less than an hour after arriving in South Korea, President Barack Obama solemnly laid a wreath at a memorial honoring Americans killed in the Korean War. On Saturday, he’ll speak to some of the 28,000 American service members stationed here and hold a rare joint security briefing with South Korea’s president.

Obama’s itinerary is aimed at showcasing the U.S. military’s deep ties to the region at a time when Asia is warily watching China’s growing military prowess and North Korea’s unpredictable nuclear efforts.

“Obviously we come here at a time when there has been provocative language from North Korea, and it’s important for us to show complete solidarity with our ally, the Republic of Korea, in standing up to those provocations,” said Ben Rhodes, Obama’s deputy national security adviser.

Obama arrived in South Korea on Friday, the second stop on his four-country swing through Asia.

Even as Obama pressed his security agenda in South Korea, he paid tribute to victims from last week’s ferry disaster. The vast majority of the 300 dead or missing were students from a single high school near Seoul.

Despite the distractions of other issues, the president’s core mission in Seoul is to underscore the U.S. commitment to the security of South Korea and other allies during a period of uncertainty in the region.