North Korean war talk: hot air or serious threat?

North Korea held a mass rally Friday with fist-shaking generals promising to “dismantle and terminate” the nation's enemies in “any part of the world”  to an audience of deliriously enthusiastic khaki-uniformed Korean soldiers.

Yet while Pyongyang’s central square looked like something out Soviet cold war days – or a throwback to the Cultural Revolution in next door China – reports from a key joint North-South industrial park at Kaesong suggested no drama and an open border with Koreans going to work quite normally. 

Still, with the North finally achieving a successful nuclear test in February, its young leader Kim Jong Un has seized the moment to raise tensions by threatening nuclear war – moving well past the status quo and routine bluster of his father, former “Dear Leader” Kim Jong Il.

Pyongyang claims it's on full military alert, ready to target US bases in Hawaii, Guam, and South Korea. It has cut the last military hot line to the South. Meanwhile, the United States sent two B-2 stealth bombers to its bases for joint exercises. But there's little sign on the ground that the North is really girding for war. What's going on?

Hasn't North Korea made these same kinds of threats for 60 years?

Threats to turn South Korea into a "sea of fire" are an old staple of the Democratic People's Republic of Korea (DPRK), the North. But the intensity and volume of this rhetoric has risen to new levels recently. "The music is the same, but is much louder," says Scott Snyder of the Council on Foreign Relations. North Korean generals are speaking about targeting the US with nuclear weapons, something unheard of a few years ago.

The North has stopped using the inter-Korean military hot lines that were part of an earlier "Sunshine policy" of reconciliation and reunification a decade ago. And for the first time in years, the South, under its first female president, Park Geun-hye, has begun to push back on Pyongyang.

New DPRK leader Kim Jung-un has had a string of rare successes. The early years of Mr. Kim's father, "Dear Leader" Kim Jong-il, were plagued by floods, starvation, and mass misery. But the young Kim has successfully tested a small satellite, and in February tested a nuclear device. (It's widely believed that the North's missiles can't yet reach the US mainland, though former Secretary of Defense Robert Gates in 2011 said the DPRK may be able to do so in five years.) North Korea may have also engineered the cyberattack on three South Korean banks in March.

Why these new threats?

The North's test of a nuclear device brought a quick and unanimous United Nations Security Council vote to step up sanctions, which enraged Pyongyang. The North says it has a right to be a nuclear power.

What does North Korea want?

Always a hot question! Ultimately, many Korea-watchers say, the DPRK wants to unify the two Koreas, North and South, under the Kim family.

The North is a family dynasty with a nearly sacred sense of its importance. Kim Il-sung, the patriarch, emerged as a self-created messianic figure out of an anti-Japanese guerrilla struggle during World War II. Both his son, Kim Jong-il, and grandson, Kim Jong-un, have wanted to get the US off the peninsula and to unify it under Kim family rule.

Yet in the short term, the North must weather and surmount its poverty, must survive as a dynasty, must find a counterweight to China (to which it owes most of its trade and economic help), and to do all this without undergoing the kind of reforms that could undermine its control of ordinary North Koreans, something made possible by its complete isolation under a police state and cultlike ideology.

In the decade after the Korean War (1950-53), a period of relative fair weather for the North, both the Soviet Union and China sought the favors of Pyongyang. But when the USSR collapsed in 1991, the North was left without a pair of patrons to play off against each other, and aid fell sharply. North Korea has long wanted a nuclear device as a prime bargaining chip. Now it has one.

What do we know about new leader Kim Jong-un?

Not very much, as is typical of other North Korean leaders. But his character and capabilities are at the core of what analysts agree is the key issue: how young Kim succeeds or fails to consolidate power.

Kim started off looking like a potential reformer. But talk of allowing new kinds of commercial nonstate trade ended abruptly in August. Since then, he has spent much of his time being visible at military installations. The power structure of North Korean society is organized around a "military first" policy. Korea-watchers worry that Kim may be too young to understand the weight of the game he is playing, or that he could be manipulated, and thus become a dangerous wild card.