The world is on edge after North Korea shelled South Korea off disputed waters. Susan Osman's guests get heated over the historic significance and how the international community should get involved.

Aired December 3, 2010

Tensions on the pided Korean peninsula have risen dramatically since international investigators said last week that North Korea was responsible for a torpedo attack on a South Korean warship in March that killed 46 sailors.

Relations are now at their lowest point in a decade. South Korea, backed by the U.S., Japan and other allies, began implementing a package of punitive measures earlier this week - ranging from slashing trade, resuming propaganda warfare and barring the North's cargo ships. Those were seen as among the strongest it could implement short of military action. Washington has promised ''unequivoca'' military support for South Korea.

North Korea meanwhile has vowed to retaliate. It has threatened all out war, cut relations with South Korea and has barred South Korean ships and airliners from passing through its territory.

China, North Korea's main ally, has so far tried to remain neutral, calling on both sides to ''exercise restraint.'' Whether or not the two sides hold off, or launch into a cross-border war is a question that's on a lot of people's minds at the moment. And it's one that's being debated online here. Let's cross to the newsroom now where our researcher Emma Wang has been gauging reaction.