The nuclear weapons enthusiast and pornography aficionado who inherited the Stalinist state known as North Korea from his daddy is dead. And no sooner did Kim Jong-il pass from the earth than his military practiced the belligerence Kim preached: It test-fired a missile. Subtle.

South Korea’s Yonhap News Agency reports that the “short-range” missile was fired into “into the sea off [North Korea's] east coast” just hours after the announcement of Kim’s death. No one appears to be hurt, and it seems that the test was planned in advance. But the message is clear enough: North Korea wants the 28,000 U.S. troops on its southern frontier to know that now is not the time to mess with it.

The South Koreans are on the same page. In the hours since Kim died, they’ve beefed up airport security, banned their citizens from traveling north, and stressed “peace and stability” with their northern neighbor. No one wants to provoke the new Pyongyang leadership at a time when its grasp on power might not be absolute, a situation that lends itself to violent miscalculation.

At the same time, North Korea has been preparing for this moment for years. The state propaganda mouthpiece dubbed Kim Jong-un, the 20-something son of Kim Jong-il, the “Great Successor” — perhaps not as catchy as his father’s Dear Leader or grandfather’s Great Leader aliases, but clearly meant to dispel the notion that Kim Jong-un has any rivals for power. No one knows if that’s actually true, because North Korea is such a closed society. But ever since the elder Kim’s 2008 stroke, Kim Jong-un has been groomed for succession, gradually gaining control of the ruling party, the military — he’s now a four-star general, despite never having served a day in uniform — and the rest of the North Korean governing apparatus.

Still, the White House isn’t leaving much to chance. A statement very early Monday morning reiterated Washington’s “strong commitment to the stability of the Korean Peninsula and the security of our close ally, the Republic of Korea.” Both countries’ national security teams are in “close coordination” to dissuade North Korea from acting out — as it did this time last year, provoking a mini-crisis over a South Korean military exercise.

But the North Korean missile launch and the Seoul-Washington responses make it seem like both sides are trying to intimidate the other out of acting rashly.

“North Korean armed forces probably are at semi-war state of alert to ensure a prompt response in the event any enemy attempts or is perceived as attempting to take advantage of a period of grief or judges the North is weakened by leadership change,” writes analyst John McCreary in his influential NightWatch security newsletter. “The longer term concern is the pressure on the new leader to prove himself.”

In other words, don’t expect North Korea’s new boychik-in-charge to suddenly agree to restart talks on giving up his father’s prized nuclear weapons program. The cost of running Stalinist regimes is knowing there’s always someone ready to kill you if you look weak.

Especially if you’re young and untested. McCreary notes that for the first time in North Korea’s history, its “new key people have no direct ties to the three wars — the anti-Japanese war before World War II; World War II, and the Korean War, which has been the cachet for leadership — and have no military training or experience.”

That kind of continuity was perhaps the one thing Kim Jong-il couldn’t guarantee. But he accelerated his own father’s legendary bellicosity. Under Kim Jong-il’s watch, North Korea became a nuclear power and an even more erratic threat to the United States, South Korea and Japan. He exported his deadly technology to fellow rogues Iran and Syria.

In his personal life, Kim enjoyed copious amounts of pornography and haute cuisine while his people starved. The official North Korean propaganda arm claims Kim died “from a great mental and physical strain” while traveling “on a train during a field guidance tour,” whatever that means. Now the strain is on his son not to blunder into a war.

Photo: Flickr/Rapid Travel Chai