On their face, they make a kind of sense. In terms of pure military force, the United States probably could do a great deal of damage to Iran’s malevolent attempt to gain nuclear weapons. But so what? The same could have been said about Iraq in 2002.

Yes, the US military did have the capacity to destroy Saddam’s regime. And it did so in three weeks. The salient question was and is: what then? It appears that the Bush administration never seriously asked that question in advance of war in Iraq and, in a stunning fit of recklessness, never made serious plans for the post- invasion.

I don’t think even Donald Rumsfeld is nuts enough not to ask that question this time with respect to Iran. The military option is much more difficult, of course. Iran learnt from Saddam’s Iraq and has dispersed its nuclear research and development sites across the country. The US cannot invade and occupy two huge countries at the same time.

If US intelligence is as good in Iran as it was in Iraq, the chances of getting all of Iran’s nuclear capacity by aerial bombing must also be close to zero. So the gain would be fleeting. But the costs could be enormous. The most pro-western populace in the Middle East — the Iranian public — could overnight be turned into permanent foes of the West. A bombing campaign could force most Iranians into the arms of the genocidal religious nutcases now running the government.

For good measure, we’d probably be faced with oil at nearly $100 a barrel; and the complete disintegration of what’s left of Iraq, as the Iranian-allied Shi’ite militias turned on US forces. But there’s another factor that makes a military attack on Iran a dangerous option for the Bush-Cheney-Rumsfeld axis. That factor is America itself.

What we’ve seen in the past few months is a cratering of support for the president. The latest Washington Post/ABC News poll confirms the pattern: 60% disapprove of Bush’s performance and 38% approve. But when you look more closely at the numbers, you find something more remarkable. A full 47% of Americans “strongly” disapprove; only 20% “strongly” approve. Half the country, in other words, don’t just disapprove of Bush; they’re furious with him.

His party is even less popular. On Iraq, the Democrats are now narrowly favoured over the Republicans — an astonishing turnaround for a Republican party whose core strength has always been national security.

To give you an idea of the shift, in December 2002, on the issue of terrorism in general, the Republicans had a 61%-25% lead over the Democrats. The numbers are now dead even.

Overall, the Democrats now have a larger poll lead over the Republicans in congressional ratings than at any time since the early 1980s.

What does this have to do with Iran? Well, imagine a scenario in which the president believes he has to bomb — maybe even with low-level nuclear warheads — the nuclear facilities in Iran. Given what we know now, it would be a very tough sell in Congress.

Without United Nations backing and solid allied support, the president would have to ask Americans to trust him — on weapons of mass destruction intelligence and on his skill in war-making. After Iraq, that’s very difficult. Americans do not listen to him any more. And they have discovered that they cannot trust him to get warfare right, or even be candid with them about it.

The president could, of course, argue that he does not need Congress’s permission to launch such a war. Good luck. A huge bombing campaign against a large sovereign country over several weeks is hard to describe by any other term than war. And the constitution clearly gives that decision to Congress. This would not be a sudden, minor mission, constitutionally permissible in emergencies. This would be the gravest decision a president could make. It would have incalculable consequences. It could unleash a wave of terrorism across Iraq and the West. It would put WMDs in the centre of a global conflict. It would alter America’s relations with all its allies and enemies. If Bush decided he could act unilaterally without congressional backing, he could prompt a constitutional crisis.

The polls show potential public backing for military action against Iran. One January poll revealed 57% supported attacking Iran if it continued to get closer to nuclear capability; 33% opposed. I’d bet that once the potential risks and blowback are debated, the gap would narrow.

In the current climate, there’s a real danger that the very debate could intensify divisions within America, with those who strongly oppose Bush refusing to back this president in any other war. An escalating nuclear standoff with Iran could, in other words, unite Iranians behind the Islamists and foment deep rifts in the United States. It’s lose-lose for the West.

Bush might find some allies. Both Senator John McCain and Senator Hillary Clinton have been very hawkish towards Iran — and they are both the presidential frontrunners for their parties.

If the Democrats take back the house or Senate, they might, ironically, feel more responsible for national security and more open to military action. All this is possible and might make some kind of attack on Iran more palatable. No level-headed person, after all, wants the Iranian regime to get nukes.

The odds, however, are stacked against Bush. When you’ve lost your own country, it’s hard to launch a war against another one. Realistically, this president can try to stall Iran as much as possible until a successor emerges who might have more credibility.

The trouble with narrowly re-electing incompetents in wartime is that, when the 51% who voted for him get buyers’ remorse, and the 49% who voted against him are angrier than ever, it becomes all but impossible for a president to gain the national unity necessary to fight and win.

And so we wait for McCain. And pray.

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