North Korean dictator Kim Jong Il died on Saturday at the age of 69 after "having a heart attack on a train," according to a state television announcement. Kim, who isolated his country and kept the world on edge with his nuclear-weapons program, suffered a stroke in 2008. Last year he anointed his youngest son, Kim Jong Eun, as his successor.

The Center for Strategic and International Studies, a bipartisan think tank, sees the event as a watershed moment. "Any expert would have told you that the most likely scenario for a collapse of the North Korean regime would be the sudden death of the North Korean leader," reads a new CSIS policy paper. "We are now in that scenario."

So what does this mean for U.S. foreign policy? The Root spoke with Ernest Bower, senior adviser and director of CSIS' Southeast Asia Program, about the significance of Kim Jong Il's death, why some people are making assumptions about the mentality of the country's young successor and President Obama's next move.

The Root: This has been called a watershed moment, but won't the regime just continue under Kim Jong Eun?

Ernest Bower: We don't know. We don't know whether the son will have the support of the military. If he doesn't, there could be all sorts of scenarios. North Korea could look substantially different in a week or in a month or in three months. We knew what it was going to look like under Kim Jong Il. We don't know what it's going to look like now because we can't safely assume that Kim Jong Eun will be able to consolidate power. And if he does or doesn't, what does that look like?

TR: If he is able to consolidate power, the speculation has been that he's just as dictatorial-minded as his father.

EB: The indications are that, but look -- he's a young guy in his mid-20s. What we know about him is very thin. Frankly, people are extrapolating and making assumptions. We don't know, the Koreans don't know and the Chinese don't know. It's that level of uncertainty in a regime that has missiles and nuclear weapons that is causing an appropriate level of high alert and focus from a security point of view.

TR: What do you make of North Korea reportedly firing a test missile into the ocean shortly after the death was announced? Was that a message?

EB: I think the message there was clearly, "Take us into account. Do not underestimate us." The regime is extremely paranoid beyond what you and I could understand emotionally based on our own experience. They have literally cloistered themselves into this shell of paranoia. With their leader dead, they probably feel extremely vulnerable, and they want to send a message that they're still there and still dangerous. Basically the message was, "Don't tread on us."

TR: In terms of a response, you say that the United States will "watch, wait and prepare." What are we watching, waiting and preparing for specifically?

EB: Well, before the death of Kim Jong Il, we were all waiting for the possibility of another North Korean provocation or aggressive act. They used this as leverage to force the world to focus on them and to bring parties to the six-party talks and others.

Watching and waiting [refers to] being unsure about whether they'll use that old tactic again to basically send a dual message of "Don't tread on us," as I mentioned before. And also the message of, "It's time to pay us some attention and give us support." But they don't know what they want, and they don't know what help they need, because I'm sure they don't know exactly who's in charge yet.

The "prepare" part means to be prepared for anything, including military action if we need to. When you don't know what the next scenario is, you literally have to be prepared for military conflict. Or maybe Kim Jong Eun is going to be a reformer. Maybe the North Koreans have been waiting for this wacko to go and want to come into the light. That's not as likely a scenario as others, but we shouldn't bet against good outcomes. That's a policy mistake that we shouldn't be making.

Cynthia Gordy is The Root's Washington reporter.