Michael Byers: The hawks are hovering. Prepare for more bombs

It is inconceivable that President Bush's advisers knew of the terrorists' plans to attack New York and Washington. And as Americans and human beings, they could not but be horrified at the countless lives lost.

Yet the hawks that dominate the Bush administration will, at the same time, see enormous opportunity in the profound outrage felt by the American people. This is the best chance they will ever get to remake the United States – and the international system – in the interests of their military establishment, and the defence industries it supports.

Their first move will consist of armed action against those whom they determine to be responsible for Tuesday's atrocities. Expect American and British commandos to be sent into Afghanistan to capture or kill Osama bin Laden. At the same time, cruise missiles and B52 bombers may well be used against the Taliban government in Kabul and Kandahar. The price of attacking America – or enabling such attacks – will be made brutally clear. If there is any hint that Iraq was involved in last week's horrors, Baghdad too will be bombed. Saddam Hussein's celebratory comments on Tuesday afternoon will have brought his country to the brink of destruction.

The immediate military response, while not specifically authorised by the United Nations, will be widely regarded as legitimate. Most governments agree that military force is appropriate in these instances, provided that it is exercised in a timely and proportionate manner and directed at preventing further terrorist attacks. In any event, few would be brave or foolish enough to oppose the United States at this time.

Having struck its retaliatory blows, the US will then shift its attention to the other countries it has deemed "state sponsors of terrorism". In the next few months, Sudan, Libya, Syria and North Korea, too, could be the targets of US attacks.

The Bush administration will also seek a dramatic increase in military spending. A national missile defence system will now be built on a scale much greater than previously planned. Such a system would have done nothing to prevent Tuesday's attacks. But the threats it seeks to address – missiles launched by rogue states and terrorists – are no longer hypothetical to ordinary Americans.

A large-scale missile defence system entails the militarisation of space. The sums involved in putting lasers into orbit are immense. But Congress, previously divided on this issue, will bow to the new mood in America. Missile defence will revert to being Ronald Reagan's "Star Wars".

The threats posed by countries such as China and Iran will attract greater attention. If a dozen individuals can wreak such destruction, the military capabilities of all foreign governments bear careful reconsideration. Ever greater amounts will be spent on cruise missiles, long-range bombers and stealth battleships – the hi-tech tools of a new fortress America.

The budgets of the CIA, FBI and National Security Agency will be increased as well. America's already extensive electronic surveillance systems will monitor an ever-greater portion of the world's telephone calls, e-mails and financial transactions. In the US and elsewhere, immigration controls will be tightened severely. Asylum-seekers will bear the brunt of these restrictions. Tuesday's attacks are already being used to justify Australia's treatment of a shipload of people fleeing the same government that harbours Mr bin Laden.

Efforts to counter terrorism in other countries will receive even greater support. The Israeli government, in particular, has already escalated its war against Palestine. Its policies of oppression and assassination are suddenly less odious to its supporters in the West. The Middle East peace process is dead. Russia's draconian efforts to stamp out rebellion in Chechnya will from now on be ignored.

In the immediate aftermath of the attacks, many of these responses might appear appropriate. The threat of terrorism is real, and may be growing. Tony Blair is right to suggest that the next attack could involve a nuclear bomb.

But America's allies will also want to consider the implications of supporting the Bush administration regardless of what it does. Do they really want nation states to lose their sovereign rights whenever the US determines they have harboured terrorists? Do they want our already fragile human liberties to be eroded further by intrusive surveillance systems? Do they want an even greater portion of national budgets to be directed to military spending? The actions being planned in Washington carry substantial risks to the very way of life they purport to protect.

Although strong action is called for, it will not be forgotten that extremism and terrorism grow out of economic inequality and civil strife. Spending limited treasure on more guns, bombs and satellites does little to address the root causes. Improved surveillance systems make us less free, but might catch only the most amateur of terrorists. Diluting sovereignty facilitates action, but might fatally undermine the United Nations.

The situation generates two competing and equally legitimate impulses: the desire to punish, and the desire to alleviate the suffering that bred this evil. America's allies will join in the effort to bring the guilty to justice. But they will also insist on non-military measures directed at making this a more equal and compassionate world.

Professor Michael Byers teaches international law at Duke University, North Carolina. He is a visiting fellow at Keble College, Oxford