The passing of the baton of leadership in Pyongyang from "Dear Leader" Kim Jong-il to "Brilliant Leader" Kim Jong-un is bad news for all those in Washington, Seoul, Tokyo and Beijing hoping to rein in the reckless belligerence of the North Korean regime. It's even worse news, and more immediately so, for any South Koreans living within ranger of the North's artillery or sailing near its waters. The track record suggests that Pyongyang's response to a generational moment of profound domestic political instability will be to lash out, unprovoked, in order to dissuade anyone from harbouring ideas about toppling the regime.
The past two decades, in which North Korea's various neighbours and adversaries have tried combinations of concessions and threats to dissuade Pyongyang from its pursuit of a nuclear deterrent, have been characterised by one overarching theme: the strategic initiative is always in North Korean hands. Pyongyang sets the agenda; the others respond. Now that it faces the harrowing test of managing the power vacuum created by the death of a personality-cult leader and his succession by an heir no older than 28, with negligible military or administrative experience or political authority, it's a relatively safe bet that the regime will seek to adjust and consolidate by rattling a few sabres. Also, there's nothing like a bracing confrontation for the "Brilliant Leader" to convince doubters within the heavily militarised regime that he can be just the sort of bully-boy his father was.
Of course, nobody serious talks about "all options being on the table" for dealing with North Korea. (Except in Republican presidential debates, of course, where the foreign policy debate is hard to take seriously.)
President George W Bush, of course, had harboured similar illusions, promising to break with the Clinton policy of negotiating economic and political incentives for North Korea to denuclearise. Within two years Mr Bush found himself forced to pursue a similar path as the Clinton administration's, in six-party talks involving both Koreas, the US, China, Japan and Russia. Unable to squeeze the concessions it sought from the US, North Korea repeatedly launched provocative missile tests and walked away from talks. Finally, in October 2006, it tested its first nuclear weapon. Even then, Mr Bush had little alternative but to return to the table.
Even before it built atomic bombs (and there's some doubt about whether North Korea's nukes have been miniaturised to fit onto missiles), the North had the advantage of having the South Korean capital, Seoul, so close by that it could be relatively quickly destroyed by conventional artillery and missiles. North Korea's leaders have believed for decades that the US and South Korea had too much to lose to risk a war, and they've repeatedly tested that proposition through sometimes outrageous provocations.
Consider: just a year ago, the North Koreans - entirely unprovoked - fired dozens of artillery shells onto the South Korean island of Yeonpyeong, killing two soldiers and two civilians. That was the first time the North had attacked a South Korean civilian population centre since 1953. And it came just eight months after the sinking of the South Korean navy vessel Cheonan, in which 46 sailors died. Oh, and lest anyone not get the message, Pyongyang also announced around the time of Yeonpyeong that it had built a new uranium-enrichment facility to enhance its nuclear weapons programme.
This is not a regime that fears military attack or sanctions - that much is clear in the horrendous living conditions it has imposed on its own people. But nuclear weapons have given it the ultimate insurance policy against regime change and it has used that position - and its neighbours' fears about its belligerence and potential to proliferate weapons technologies - to force the hand of its adversaries.
The Obama administration had hoped that a policy of "strategic patience" - effectively malign neglect through economic strangulation and otherwise ignoring Pyongyang - would contain North Korea, while insulating the president from the political risk of engaging. North Korea tested a second nuclear bomb during Barack Obama's first year in office, and sharply escalated its provocations the following year. Plainly, the policy wasn't working. Nor has the habit of both the Bush and Obama administrations of trying to shame China into shackling North Korea paid any dividends. China has its own menu of interests, including preventing collapse of the regime and a flood of refugees across its border, and also to avoid thus establishing a potential US foothold on its own border.
So, the bitter reality is that incentives, rather than pressures, remain the key to changing the dynamic with North Korea. Indeed, after a series of back-channel contacts, the administration was making progress with North Korea in new talks, previously scheduled for this week, over exchanging food aid for undertakings on denuclearisation. Even then, it seems unlikely that any North Korean leader will entirely give up a key source of the regime's outward strength. The grim reality is that Kim Jong-un and those helping him consolidate power will feel they need North Korea's nuclear deterrent even more than his father did.
The death of Kim Jong-il ends any diplomatic progress in the next year, at least. Also, the US has an election, and concessions to North Korea don't play especially well. Indeed, previous economic aid for denuclearisation deals have been hamstrung by the US Congress. China, too, is entering a year of leadership transition, while South Korea also votes for a new president a year from now. None of those changes facilitates diplomatic progress, but North Korea's own leadership change trumps them all.
North Korea on Monday marked Kim Jong-il's death with the desultory test-firing of a missile off its east coast. That's somehow unlikely to be the last such bit of sabre rattling of the mourning season.
Tony Karon is an analyst based in New York. Follow him on Twitter @TonyKaron