I can hardly believe that a majority of British MPs will tonight vote to renew the British nuclear deterrent. Almost all of them, of all parties, know in their heads that it makes no sense. They lack the guts to say so, Labour MPs because they want jobs under Gordon Brown, Conservatives because they love whizzbangs and want to embarrass Tony Blair by keeping him in power, for reasons that pass comprehension.
There is no surer sign that the Trident missile system is strategically obsolete than the archaic arguments ranged in its support. It is said to be the ultimate weapon. We have got it and may as well keep it. It is an insurance policy against "the unknown". You never know what the terrorist might get up to. You can't trust the Americans. Trident keeps us a place at the top table.
Unlike Blair, I thought unilateral nuclear disarmament during the cold war was misguided. At a time when two centralised states, America and the Soviet Union, had large nuclear arsenals poised in equilibrium, keeping that balance required precision discipline, as did their subsequent dismantling. In 1982, Blair said that to reject unilateralism would be "an error of enormous proportions". He was wrong and irresponsible. Multilateral disarmament yielded treaties on arms reduction and nuclear non-proliferation that helped end the threat of communism and made the world incomparably safer, more than can be said for the west's present generation of leaders.
Half the Labour members of the House of Commons, including the prime minister, were members of the Campaign for Nuclear Disarmament. They must surely acknowledge that the spirit, if not the actual letter, of the nuclear non-proliferation treaty requires Britain to decommission Trident. While that may make no difference to the nuclear ambition of North Korea or Iran, the sheer hypocrisy of Britain preaching a non-nuclear world while preparing to spend a staggering £70bn buying and running new long-range missiles, warheads and submarine platforms is breathtaking.
Trident is like the Olympic games or ID cards, projects whose mindless extravagance stretching beyond parliaments puts them out of reach of sane value-for-money accounting. They demand a quasi-religious "justification by faith", supported by a baying priesthood of weapons contractors, publicists and BAE lobbyists. Trident worshippers are a mystical freemasonry, seemingly obsessed with priapic enhancement and ancestor worship. Their concern is with prestige, not with defence.
The case against Trident hardly bears repetition. Its value as a deterrent depends on a coherent enemy with a leadership capable of being deterred. This applied to America and Russia in the cold war. That is now over. Even if Nato restarted it by reckless meddling in southern Asia and the Caucasus, Britain's use of nuclear weapons in such aggression would be unthinkable. As for the west's nuclear shield, that would continue to be supplied by America.
The truth is that the west's nuclear status has not deterred any aggressor. It did not deter North Vietnam from invading the south, Galtieri from invading the Falklands, Saddam Hussein from invading America's ally Kuwait, Syria from invading Lebanon or Milosevic from massacring his fellow Yugoslavs. It does not matter how devastating a weapon is. If its use is inconceivable, its deterrent value is zero.
These wars were won by troops seizing and holding territory with conventional weapons, which have not changed qualitatively in half a century. Those that pose the biggest threat to the British army are the AK-47 (celebrating its 60th birthday), the rocket-propelled grenade and the explosive roadside device. When these are allied to the suicide bomber, the fanatical preacher and global 24/7 media manipulation, western forces seem to have no answer.
The wars being fought by the west's current leaders are "fourth generation" wars, post-conventional, post-nuclear and post-guerrilla. They are not against states but against groups, insurgencies and public opinions. They are fought in cities and through the media, pitting terror against normalcy and surveillance against liberty. They confuse the boundary between civil and military operations. Defence against such aggression requires diplomacy, espionage, special forces and, I have no doubt, secret ruthlessness.
The idea that a nuclear weapon might influence such conflict is absurd. Even in the unlikely event of a terror group being able to steal, mobilise and arm a nuclear device, it would not be deterred by a threatened nuclear strike against some distant state. Britain and America dealt a supposedly devastating blow against "terror" by toppling the governments of Afghanistan and Iraq. The effect has been counter-productive. The greatest danger of nuclear weapons is that they tend to make their owners think themselves omnipotent.
The non-proliferation treaty is being shot to pieces by America appeasing the nuclear ambitions of Israel, India and Pakistan and goading Iran's fundamentalists into wanting a bomb too. These states want bombs not to threaten the west but, as with the east-west balance in the cold war, to balance regional deterrence. We may not like this but we can't stop it; nor does it threaten Britain or the non-nuclear states that comprise most of the world. We have lived with this appalling weapon for half a century, in which it has never been used in anger. The genie is out of the bottle, and diplomacy is her most effective chaperone.
Trident renewal is a classic example of generals fighting the last war but one. Any fool can claim that a nation must be armed against any contingency. But this is a platitude, not a policy. Sound defence is built on prediction and proportion, and must work to budget. Were there money to burn on defence procurement, soldiers might welcome all the kit in the world. As it is, Britain's forces are plainly short of the most basic equipment. In Iraq and Afghanistan the army has reportedly been short of helicopters, safe troop carriers, radios that work, body armour and boots. Above all it has been short of soldiers.
I might argue that we should not be fighting these wars, but we are, and those who support them have an even greater responsibility to adjust the defence budget to their priorities. Trident is not remotely a priority. It is a white elephant left over from a war that is past and won. Renewing it for a hypothetical war can only impede the army in fighting one that is all too real. How can any responsible MP vote for it?
By Simon Jenkins