But the point of the vast array of force is not military, it is political. Just as the United States envoy Richard Holbrooke used the threat of force to bring the Yugoslav leader to the negotiating table over Bosnia in 1995, the aircraft are a prop in a tough power game that is being played out in the conference rooms of Belgrade.
Mr Holbrooke and Mr Milosevic are old sparring partners - indeed they are said to be on first-name terms. During the epic Dayton negotiations, which brought a settlement of the Bosnian war, they shared more than one mid-morning slivovitz.
The Yugoslav President has been under no illusion about the relentless and dictatorial Holbrooke style: indeed in the ruthlessness of the man across from him, and his utter lack of sentimentality, he can only have seen reflections of himself.
The Holbrooke modus operandi is a bewildering mixture of cajoling and bullying. He will shout and bang the table. When he called the marathon 11-hour session with Mr Milosevic, which stretched into early yesterday morning, intense and heated, that will have been an understatement.
Belgrade 1998 has, in many respects, differed from Dayton 1995, but in one crucial sense it is similar. Both negotiations were under the gun.
Three years ago, the protagonists of the Bosnian conflict were taken to the Wright- Paterson airforce base and told unabashedly by Mr Holbrooke that they would not be allowed to leave before a deal was done. It was.
The same has been happening in Belgrade for the past few days. Mr Milosevic may equivocate and procrastinate about the composition of a peace-keeping force in Kosovo, but he too knows that he must reach a deal - unless, of course, he has calculated that air strikes by Nato are the lesser evil. With Richard Holbrooke, there is no avoiding the moment of truth.
The plan to launch a graduated air assault on Serbian targets, inside and outside Kosovo, has been widely disseminated, part of the strategy of piling political pressure on the Yugoslav leader. The publicity given to the air build-up has been considerable, stretching from television shots of B-52 bombers arriving in Britain from the United States to news that six A-10 tankbusters have been redeployed from Germany to Italy. This is military force on a declaratory scale, the modern equivalent of sabre-rattling.
An aerial armada of some 460 aircraft has been assembled for the attacks, which will consist of fighter cover, bombers, aircraft with anti-radar missiles and electronic early warning aircraft.
If Mr Milosevic refuses to yield, then Nato nations would issue the activation order to hand over operations to the military. Phase Zero would involve reconnaissance flights that staked a claim to Yugoslav air space - a further piece of political pressure.
The next phase would involve a series of targeted attacks on military targets by cruise missiles launched from the B-52 aircraft stationed in Britain and vessels currently on exercise in the Adriatic on Operation Dynamic Mix.
The targets would be command and control sites and air defence batteries. It would be a step up the ladder, but well short of a war, still aimed principally at intimidating.
If this were not enough, then Nato would go further, hitting targets inside and outside Kosovo, with massive air power. But soon there will come another set of even more difficult decisions. Air power can intimidate, but it cannot change the facts on the ground.
If Mr Milosevic agrees to a deal, then it will be necessary immediately for the Western powers to agree on a land force to monitor agreement and assist the 300,000 refugees. This could be a lightly armed force of perhaps 1,500 people, backed up by the threat of air power from outside and a rapid reaction force based in the region. The aircraft which have been deployed to the region would remain as the guarantor of security for the forces in Kosovo.
At this stage, the linkages between military power and diplomacy become more difficult. The US does not want to put ground troops into Kosovo, just as it did not into Bosnia.
Sandy Berger, President Bill Clinton's National Security Adviser, has said that no American combat forces would be involved in the more lightly armed group, which "would be largely civilian". If, however, a larger deal is brokered on autonomy for Kosovo, that might need to be augmented, but again Mr Berger said it "ought to be largely European".
In the event that Mr Milosevic does not yield, the threat of force will be maintained. Nato will be ready to strike at any time.
But even if the vast wave of air power were to be unleashed, it would not solve the problem of Kosovo. Aircraft cannot hold territory; and as the US operations over Iraq have shown, merely patrolling the skies is not in itself an end to a political deadlock. Nato would have to follow on from an air assault to a ground operation, and the troops would need to be far better armed, and capable of fighting their way out of trouble.
The threat of air power has been deployed as the companion to diplomatic pressure, with the aim always political - an end to the fighting - rather than purely military.
At some stage in the next few days, whether Mr Milosevic yields or not, the conclusions will have to be drawn from this - that land forces will follow the air armada, bringing troops from the main European powers, including Britain and France. That is when the really hard decisions will have to be made.Reuse content