Air superiority secured through the new generation of 'fire and forget' weapons

After a week in which bombs and cruise missiles have rained down on Afghanistan, military officers and political leaders of the coalition ranged against the Taliban and its ally, Osama bin Laden, will be asking: what has been achieved so far?

The answer is that the first military aim, air supremacy, has been attained with ease. When it comes to the overall goal – killing or capturing Mr bin Laden, dismantling his al-Qa'ida terror network and destroying the Taliban's ability to support them – the results so far, not surprisingly, are less clear-cut.

Despite heavy attacks on command targets and terrorist training camps, in which some of the Taliban leaders are reported to have been killed, most are no doubt in hiding or on the move. But US and British forces have clearly destroyed most of what there was of an air defence system in Afghanistan.

Bombing was suspended briefly on Friday, the Islamic holy day, but resumed after midnight. By today there will have been seven successive nights of bombing. The first targets, as always, were air defences – radars, missiles, the few Afghan aircraft on the ground and the airbases from which they might operate. Cruise missiles, fired from US B-52 bombers or Navy cruisers and Royal Navy submarines, were used against big, static targets, clearing the way for more agile fighter bombers, including carrier-launched F/A-18s, to strike more elusive targets. By Tuesday, US aircraft were launching daylight attacks, suggesting that air supremacy had been achieved, enabling the Americans to bomb at will.

So far there have been no reports of the Taliban forces using the feared Stinger hand-held anti-aircraft missiles supplied to the Afghan mujahedin by the CIA during the Soviet occupation in the 1980s. This could mean the Taliban are holding them back for use against more vulnerable and politically lucrative targets; high-flying aircraft, mostly at night, are not the best targets for Stingers. But without proper maintenance over the past decade or more, these missiles may have deteriorated significantly.

The US has also used laser-guided bombs, which appear to have performed better than in any previous campaign. A photograph of an Afghan airfield last week showed holes drilled very precisely at all the main intersections between the runways and taxiways, indicating the extreme care taken to identify the key parts of the target, as well as the accuracy of the bombs.

A new weapon, employed for the first time on any scale, is the Joint Direct Attack Munition, or JDAM. Like a cruise missile, it is pre-programmed with the co-ordinates of the desired destination, accurate to within 30ft or so, and when released, steers itself to that point. This "fire and forget" weapon obviates the need for a pilot to keep a laser trained on the target for agonising seconds. The US has also been using so-called "bunker-busters" – able to penetrate 20ft of concrete or 100ft of earth – to shatter underground installations.

On Thursday night correspondents with the Northern Alliance reported the explosions on Bagram airfield, north of Kabul, were much bigger than any seen before. Bagram would be a valuable base for any land operations and it is unlikely that the US would want to destroy it. The distinctive bursts reported were probably from fuel-air explosives, which generate a blast effect over a wide area. This weapon would be used to kill Taliban troops around the airfield and detonate any mines they had planted, while leaving the installations intact for capture by US-led forces, the Northern Alliance, or a combination of both.

How much military help is being given to the Northern Alliance is unclear. There are reports that the US is refraining from heavy air attacks north of Kabul, lest the alliance, considered a poor basis for a future Afghan government, be given an easy passage into the capital. But the attacks have probably destroyed the Taliban's ability to keep its northern garrisons supplied by air, making them highly vulnerable to capture.

General Richard Myers of the US Joint Chiefs of Staff has said repeatedly that only a small part of this operation is visible. Special forces are almost certainly already in Afghanistan, but primarily for liaison with local forces, to gather intelligence and to report on the effects of the air strikes. It is unlikely for the moment that they are taking any direct part in the fighting.

So what is the next step? Allied aircraft can now operate in relative safety, and in daylight, as long as they stay out of range of the smaller anti-aircraft guns and hand-held missiles. To achieve the next stage, air control, in which there was virtually no threat to air forces, ground troops would almost certainly have to be deployed to occupy and secure areas of Afghanistan. That is a big step: in the short term the coalition forces are likely to redouble their efforts to bomb al-Qa'ida and the Taliban off the map.

One of the first attacks last week was on the empty home of the Taliban leader, Mullah Omar, in the centre of Kandahar. Although the house had been empty for two years, it was built by Mr bin Laden's construction firm. The message delivered was unequivocal: this is personal.

Christopher Bellamy is professor of military science and doctrine at Cranfield University