Will the Korean War break out again?

The Korean War of the 1950s has never officially ended.  Now South Korea, after decades of restraint, is getting tough with its Stalinist neighbor to the North, responding to a deadly torpedo attack on one of its ships that killed 46 South Koreans:

South Korean President Lee Myung-bak said Monday that his country is stopping all trade and most investment with North Korea and closing its sea lanes to North Korean ships after the nation's deadly attack on a South Korean warship.

Lee also called for a change in the North’s Stalinist regime.

The tough measures, announced in an address to his nation, were bound to ratchet up pressure on the isolated Pyongyang government and add a new flash point in U.S. relations with China.

“Fellow citizens, we have always tolerated North Korea’s brutality, time and again. We did so because we have always had a genuine longing for peace on the Korean Peninsula,” he said. “But now things are different. North Korea will pay a price corresponding to its provocative acts.”

Lee then said that “no North Korean ship will be allowed to make passage through any of the shipping lanes in the waters under our control” and that “any inter-Korean trade or other cooperative activity is meaningless.”

via South Korea to halt all trade with North Korea over sinking of Cheonan warship.

In the meantime, American forces have announced a joint military exercise to put on a show of force designed to “deter North Korean aggression.” The big question is what China will do. The even bigger question, of course, is what North Korean dictator Kim Jong Il will do. He has threatened war over lesser confrontations and is utterly unstable and unpredictable. And he may have nuclear weapons.