Are we headed for a new Korean War? Not just skirmishes, sabre-rattling or a torpedo in the night, but a full-blown armed conflict on the Korean Peninsula?

You would be forgiven for thinking so if you've followed the drumbeat of headlines since the 13 February nuclear test or even last December's missile launch. Some serious analysts are stressing the possibility of war. Some are even underlining, too much in my view, the risk of escalation to the use of nuclear weapons.

I would put the analytical focus on a somewhat different place. Deterrence is alive and well and at home, for better or worse, in the Asian century.

Yes, those warning of war have a point. An iconic act of limited aggression by the North is a real possibility. Kim Jong-un obviously feels he has lots to prove, and a fresh act of violence like the 2010 sinking of the Cheonan or the bombardment of Yeonpyeong Island might just do the trick. Yes, the South has promised to respond forcefully to any future such provocations, and the US and possibly others would feel compelled to back it up. Yes, the young Kim has thrown fairly much every toy out the cot this time, and needs a face-saving way to quieten down.

But I still assess, on balance, that the North Korean leadership is aware of the risks of a spiral into the war, which would seal its fate. Why else, after first promising nuclear attack, has Pyongyang lurched back to rather less apocalyptic threats, such as restarting its Yongbyon reactor or obstructing South Korea workers at a joint project? As for ordinary North Koreans, it's not clear that they think Armageddon is just around the corner.

The fate of North Korea is less likely to be about a high-definition replay of the 1950-1953 war than about change from within and eventual regime failure leading to some seriously dangerous moments for US-China diplomacy (as explored in Chapter 5 of this Lowy Institute report). 

So for the moment I would play down the war talk. I put a small-scale North Korean attack in the 'possible' basket, an escalation to large-scale conventional conflict in the 'highly unlikely' basket, and the chance of nuclear escalation pretty much as remote as it has been for decades (which is not to say it is impossible).

If the Korea crisis of recent weeks underscores one reality it is the central and continuing role of deterrence in Asia's security. It exposes in plain sight – as plain as last week's much-publicised B-2 'stealth' bombing run – the unpleasant fact that the security and prosperity of the Asian century still rests on the existence of American military power and a professed willingness to use it.

The talk and action coming from Washington at present is about reinforcing the credibility of so-called extended deterrence – America's capability and willingness to use force, including nuclear force, to protect its allies. This is not the Asian century Australia's economic optimists had in mind when they wrote Canberra's eponymous white paper.

As I have explored with colleagues in a major international study on the subject (including a research workshop in Seoul on the day the North bombed Yeonpyeong Island) the toughest audience to convince when it comes to extended deterrence is not the adversary, it is the ally. A parallel debate on this blog reached much the same conclusion.

Much as some may comfortably decry America's supposed obstinacy, the fact is that the US extended deterrent is doing us all a favour by keeping a lid on the other North Asian nuclear proliferation genies: South Korea and Japan.

Bear in mind that two-thirds of South Koreans claim to be in favour of their country building its own nuclear weapons, presumably out of concern that the US cannot really protect them. And the possibility of Japan eventually following that path is not to be discounted, even though the politics of it would tortuous. Japan already has the scientific infrastructure and the plutonium stockpile it needs.

The good news is that there is no nuclear arms race in North Asia now. If Tokyo and Seoul definitively lost faith in Washington, there would be. Indeed, the effect would cascade right across the Indo-Pacific, for China could well build up its presently modest nuclear arsenal if it faced a nuclear Japan, and India would end its relative nuclear restraint if China did (Pakistan seems to be going hell for leather with its nuclear program anyway).

None of this means that the US should lightly brandish its overwhelming nuclear capabilities or issue matter-of-fact pronouncements about a readiness to use them. Thankfully it is not doing those things. President Obama's Administration is arguably the most morally troubled by America's possession of nuclear arms of any administration since the Bomb was invented.

Obama has done sane, practical, realistic things to reduce the size of the US nuclear arsenal and the role those catastrophic weapons play in global security. In recent months, there have been rekindled discussions within the Administration about possible new reductions to America's strategic arsenal.

But it is likely that the current Korea crisis will put that push on hold, to avoid unnerving the Asian allies. However cautious the language ('everything necessary') or ambiguous the signals (a B-2 can carry conventional or nuclear bombs), the posturing of extended deterrence is back. It's now a part of America’s Asia pivot. No wonder China is getting worried and perhaps even rethinking its creaking North Korea policy.

Photo by Flickr user US Army Korea (Historical Image Archive).