Afghans flee in fear of Bush's firepower

Without a shot having been fired, the prospect of international revenge for the carnage in New York and Washington has thrown Afghanistan into turmoil.

Growing fears of an attack on the country harbouring Washington's prime suspect for the worst act of terrorism in history, Osama bin Laden, have not only caused United Nations staff to leave for Pakistan, but also large numbers of ordinary Afghans to quit Kabul and other cities.

The US and its allies have a formidable array of weapons and forces which could be used against Afghanistan's fundamentalist Taliban regime in what President George Bush has called "the first war of the 21st century". They range from cruise missiles and aircraft carrier groups to B2 stealth bombers and elite special forces. According to military experts, US and British special forces such as the SAS and US Delta Force may already be stationed at bases such as Diego Garcia in the Indian Ocean or Cyprus in readiness for a raid on Afghanistan or covert intelligence-gathering and bomb-targeting missions.

Pakistan is under intense pressure to come down unequivocally against terrorism, but demands that it should allow a large Western force to be based on its soil would bring the military president, Pervez Musharraf, into confrontation with his own Islamic hardliners. Such a force would be vulnerable to terrorist attack long before it reached the Afghan border, and the experiences of the Soviet Union in the 20th century and Britain a century earlier underline the dangers for would-be invaders of Afghanistan.

It would be far easier for General Musharraf to comply with American demands to close the border with Afghanistan and allow US aircraft to overfly Pakistan, as well as co-operating more discreetly with special forces rather than conventional forces. Highly sophisticated spy and reconnaissance satellites will already be positioned over Afghanistan and the Middle East, watching Mr bin Laden's known bases and scouring the area for unusual activity. But Pakistan, the country which gave birth to the Taliban, is best equipped to supply the crucial intelligence Washington needs to locate Mr bin Laden, his followers and their training camps. Without this, none of the options – heavy air bombardment, precision bombing by cruise missiles and laser-guided bombs, or an incursion by special forces to kill or kidnap Mr bin Laden and other senior terrorist leaders – will be effective.

Professor John Garnett, director of the Centre for Defence Studies at King's College London, said it was possible that the mere threat of military action would intimidate the Taliban into handing over Mr bin Laden. If this failed, then selective and precise bombing by cruise missiles would be the next option, followed by similarly selective special forces action. But he too stressed the importance of good information.

The US and Nato lacked evidence about the identity of the perpetrators, which apart from Mr bin Laden and Afghanistan could involve radical Islamic groups in Pakistan, Bekaa Valley in Lebanon, Algeria or other parts of the Middle East or north Africa. State backing from Saddam Hussein's Iraqi regime is another possibility.

"There are three critical questions," said Prof Garnett. "Who did it? Why? And what are the consequences of action? We don't know the answers. If they hit the wrong target and if they respond illegally, or in a disproportionate way, then all the sympathy which exists now for the United States will evaporate. It is not a time for rash action."

Paul Wolfowitz, US deputy defence secretary, stressed that Washington would not rush into action, saying: "It's going to unfold over time ... It will be a campaign, not a single action." But when action came, it would be devastating. "It's not just a matter of capturing people and holding them accountable," he said, "but removing the sanctuaries, removing the support systems, ending states who sponsor terrorism."

The US has called up 50,000 reservists and voted billions of dollars for the anti-terrorism effort, but military planners have a range of assets immediately available in the region of the Middle East and central Asia, including three US aircraft carrier fleets, one in the Mediterranean, one in the Gulf and one on standby in the Indian Ocean. Coincidentally, at least 24 Royal Navy ships, including the carrier HMS Illustrious, and 20,000 British service personnel are gathering for a long-planned exercise off Oman. Both the British and American naval forces can fire cruise missiles, and US and RAF bombers are permanently stationed in Turkey, Italy and Saudi Arabia.

The US has numerous examples before it, however, of attempts to punish terrorism which have failed because of intelligence shortcomings or hasty planning. Two weeks after US embassies in east Africa were bombed in August 1998, President Bill Clinton ordered 70 cruise missiles to be fired at Mr bin Laden's terror training camps in Afghanistan. Mr Clinton was accused of making the strike to distract attention from the Monica Lewinsky scandal, then at its height. Whether that was true or not, Mr bin Laden was not only unscathed, but saw his reputation among Islamic militants enhanced.

Special forces assaults carry their own dangers, however. The Rangers, one of the toughest units in the US military, completely botched an attempt to arrest a Somali warlord in Somalia in 1993, losing 18 men. The body of a helicopter pilot being dragged through the streets of Mogadishu completed American humiliation and prompted a hasty withdrawal from Somalia. Even more relevant is the disastrous failure of an attempt to rescue the hostages in the US embassy in Tehran in 1980, dealing a death-blow to President Jimmy Carter's chances of re-election.

Colonel Philip Wilkinson, a retired officer with commando and special forces experience, pointed out that Israel had had little success countering Palestinian suicide bombers with tanks, helicopter gunships and artillery. "This isn't a military challenge per se," he said. "This is a political and ideological challenge. I would like to think a military response would be just one important thread of the strategic response."