I love a good debate. I can think of few issues so contentious in international relations as ballistic missile defence.

Well, that's not true. There are lots of issues just as contentious, but ballistic missile defence is one of those issues that certainly evokes strong opinions from all angles. I think it is also a very useful subject for debate for those interested in getting down to core assumptions and values in international relations. Do you value diplomacy or capability? Treaties or hard power? Offence or defence? Containment or deterrence?

I have been a fairly consistent supporter of former US president George W. Bush's plans for a BMD shield in eastern Europe. I recently wrote a post on this. I find the issue so interesting, in fact, that I have written a newspaper article on the subject which will appear in tomorrow's Guelph Mercury and which I will paste to this space just as soon as it hits Al Gore's series of tubes (known to technical types as "the interweb").

Now, I'd like to set up the debate a little put, and give others some fodder for generating discussion.

Here is a Bulletin of the Atomic Scientists. In this piece, distinguished nuclear policy analyst Pavel Podvig argues that BMD is a silly idea.

... missile defense will never live up to these expectations. Let me say that again: Missile defense will never make a shred of difference when it comes to its primary mission--protecting a country from the threat of a nuclear missile attack. That isn't to say that advanced sensors and interceptors someday won't be able to deal with sophisticated missiles and decoys. They probably will. But again, this won't overcome the fundamental challenge of keeping a nation safe against a nuclear threat.

Well, how come, Mr. Podvig?

 ... because it would take only a small probability of success to make such a threat credible while missile defense would need to offer absolute certainty of protection to truly be effective.

Why, though? According to Mr. Podvig, during the Cold War everybody knew missile defence was a silly idea because it couldn't possibly protect either protaganist - the US or the USSR - because each would be raining down hundreds, maybe thousands, of nuclear warheads on the other in the event of a strategic nuclear exchange.

But things have changed. There isn't a lot of buzz out there about a US-Russian nuclear exchange. ABM defence is predicated upon the need to protect against missile attacks from rogue states like Iran and North Korea. According to Mr. Podvig and others, missile defence is reasonably capable now, and will be increasingly capable in future, of neutralising the threat of nuclear missile attacks from rogue states. But he doesn't care.

Why?

Would missile defense change Washington's strategic calculation in a potential conflict with North Korea or Iran? The answer to this question is a firm no.

He raises a very important point, here, though it is not decisive in my view. It is possible that nuclear threats of any variety would never be so certain to be neutralised by ABM shields that strategists woudl have to assume the nuclear warhead would be delivered and detonate. In this sense, who cares whether there's a shield? It's never gonna be so fool-proof that strategists will cease to assume that a threatened nuclear missile attack would be unsuccessful. And on a somewhat unrelated note, would ABM shields not induce a normalisation of nuclear threats? Would the assumption of nuclear hostility perhaps become a self-fulfilling prophecy, and have the effect of de-sensitising us to nuclear dipomacy and threats? Would this not erode the norm against nuclear proliferation and therefore threaten the entire international non-proliferation architecture?

Well, none of these questions can be answered cleanly.

Regardless, I think I would respectfully challenge Mr. Podvig to flesh his logic out a little bit more. In the event that a rogue nation (by the way, do you think the idea of 'rogue states' is silly?) wanted to commit nuclear blackmail (do 'x' and we will de-escalate tensions with neighbour 'y', whose security you value), an effective ABM shield could conceivably deter this behaviour in the first place by making 'prospects of success' prohibitively low for the aggressor. Or, say, in the event Iran acquired nuclear weapons and sought to threaten its neighbours in its pursuit of regional hegemony, ABM defence could provide US allies with another layer of security on top of other security guarantees and western commitments to non-proliferation in the middle east. ABM defence could help steady regional allies in north east Asia who (i.e., South Korea and Japan) who have hitherto shunned nuclear weapons believing firmly in the will and ability of the US to defend them from those nutters in Pyongyang. (Of course, we're talking about eastern European ABM defence here and not north east Asian ABM defence, but the logic holds.)

To my mind, ballistic missile defence is an important tool to help ensure the security of democratic peoples throughout the world, who turn to the United States and its allies for security and leadership. It is an important approach to diminishing the prestige associated with nuclear armament, because small arsenals would be much less effective in the presence of a robust ABM system. Tactical nuclear exchanges would be less likely to happen in operational theatre by what Project for a New American Century types refer to as "smaller, adversarial states".

And BMD has important political advantages. It makes it clear to Russia that its expansionist impulses are not acceptable. It makes it clear that the US remains serious about protecting middle eastern and other global allies from the threat of nuclear blackmail. It extends US and western military dominance far into eastern Europe and north east Asia by deeply entangling the security of our allies in these regions with the foreign and defence policy of the United States. Ballistic missile defence provides an important opportunity for states in rough neighbourhoods (Poland, Czech Republic, Japan, South Korea, perhaps certain or many middle eastern states) to very clearly indicate their deep alignment with US and allied foreign and defence policy, and brings with it an element of permanence because ABM shields require significant technical knowledge sharing and serious, long-term decision making by host governments.

Anyway, just thought I'd 'tee up the debate', as it were.