WASHINGTON  President Obama was awakened at 3:55 a.m. Tuesday to a fresh foreign policy problem: North Korea 's deadly artillery attack against a South Korean island.

It wasn't enough of a disaster to change Obama's plans for the day — a trip to Kokomo, Ind., to talk about jobs and the economy and an interview with ABC's Barbara Walters— but it prompted a scrambling of top national security aides in Washington, plans to call to South Korean President Lee Myung Bak and a new look at where North Korea sits on his administration's list of priorities.

"Traditionally, North Korea has not been a top-tier problem, but events like this need to make it a much higher priority," said Victor Cha, a Korea expert at the Center for Strategic and International Studies. "This is close to conventional war in Asia. This has to become a top-tier problem for the administration."

The White House response made clear the president and his advisers took the latest act of aggression from North Korea — the shelling of the tiny island of Yeonpyeong — seriously:

•On Air Force One, White House deputy press secretary Bill Burton told reporters that "the president is outraged" by North Korea's aggression and committed to South Korea's defense.

He said Obama was awakened by a phone call from national security adviser Tom Donilon.

The White House put out a statement condemning the attack about a half hour later, at 4:33 a.m.

•In the Situation Room at the White House, at least 20 of Obama's top national security aides, including Defense Secretary Robert Gates and Secretary of State Hillary Clinton, convened at 4 p.m. ET to discuss the matter. Also at the meeting: Adm. Mike Mullen, chairman of the Joint Chiefs of Staff, U.N. ambassador Susan Rice and James Clapper, the Director of National intelligence.

Obama dropped by the meeting when he returned from Kokomo.

• At the White House, Obama was scheduled to call Lee — who would just be waking up — at 9 p.m. ET to confer.

• In his ABC interview scheduled to air Friday, Obama said the threat from North Korea is "serious and ongoing" and "needs to be dealt with." He urged China to to communicate to North Koreans "that there are a set of international rules they need to abide by."

Burton said that "North Korea is not living up to their obligations and they ought to live up to the obligations signed in the armistice agreement" in 1953 at the end of the Korean War.

The communist regime also needs to halt its "illegal nuclear program," Burton said, just days after Stanford University scientist Siegfried Hecker, a former director of the Los Alamos National Laboratory, reported that he had discovered a new uranium enrichment facility.

Janne Nolan, head of nuclear security programs at the American Security Project, a non-partisan think tank, and author of Guardians of the Arsenal: The Politics of Nuclear Strategy, said North Korea's latest provocations are "not a crisis for Obama per se" but rather "an ongoing persistent problem that the international community has been trying to address for decades."

On the nuclear issue, she said the U.S. government shouldn't be cowed. "We were ready to face down 10,000 nuclear weapons from the Soviet Union," Nolan said. "We should be able to deal with North Korea."

At the conservative Heritage Foundation think tank, Asian Studies Fellow Bruce Klinger said the Obama administration hasn't put enough emphasis on the North Korea problem.

Obama has committed to Mideast peace talks that are "going nowhere" and a new arms-reduction treaty with Russia that "has no advantages" for the United States, he said. In doing so, the administration has sent "messages to the Iranians and the North Koreans that they're not at the top of his radar. … One could argue that that's why they're becoming so aggressive."