Before the attacks were suspended on Thursday night, Nato aircraft flew about 3,400 sorties, of which about 750 were attack missions against ground targets. Nato attacked a total of 56 "targets", within which there were 350 "aiming points" - individual sheds, warehouses, radars, command bunkers.
Officially, these attacks had nothing to do with the collapse of Bosnian Serb resistance in the face of Croat and Muslim attacks last week. Indeed, Nato avoided hitting Bosnian Serb front-line troops, partly because those targets are much more difficult to hit, and partly to avoid accusations that they were directly helping the Bosnian government forces .
But Nato took out the Serbs' most valuable cards, negating their most decisive advantages. Nato attacked the Serbs' ammunition and armaments manufacture and repair facilities - their most obvious advantage over the more numerous but less well-armed Muslims.
But, more important still, Nato punched out the Serbs' eyes and the nervous system of the Serb military machine. And one of the areas they concentrated on was around Banja Luka, where there were strong air defences - the area where the most recent Croat and Muslim advances have since taken place.
It was, in fact, the senses, nerves and reflexes of the Serbs' military machine, rather than its muscle, which made it so powerful. Until this year, the Bosnian Serbs showed themselves to be better than their enemies at co-ordinating the movements of large formations, widely dispersed over the mountainous terrain. Orders to open or close routes to UN convoys passed relatively efficiently. Other orders and intelligence passed equally swiftly, enabling the Serbs to hold their thinly defended lines against large concentrations of Bosnian government troops.
If you wanted an idea how good the Bosnian Serbs' command and control system used to be, you could have tried giving 24 hours' notice of your intention to pass through the Bosnian Serb checkpoints on the way into Sarajevo. By the time you reached the checkpoint the next day, you might find the Serbs clutching faxes of any articles you had published in the previous few days.
Nato's first priority was to disable the Bosnian Serb air defence network. That not only meant destroying individual radars and missile launchers, but dismantling the system, so that early-warning radars could not alert missile batteries further back. By last week, Nato assessed it had succeeded.
But cutting the system linking the air defences meant cutting other communications. On Friday UN aid workers confirmed that their attempts to assist Serb refugees streaming north towards Banja Luka were hampered by damage to the civilian telephone network. Nato had not just disabled the air defence system. It had disabled the entire state structure of Republika Srpska.
Without command and control, any army is like a headless chicken. The "indirect approach", beloved of strategists from Sun Tzu in the 5th century BC onwards, involves severing these links, so that forces cannot talk to each other, cannot receive orders, cannot receive warning of enemy attacks.
Perhaps the clearest example came from the Gulf war, where, after the command system was destroyed in the air campaign, the Iraqi field forces were unable to react to the ground offensive, paralysed like a rabbit in headlights.
Nato sources on Friday said they had been aware that attacks on the Serbs' command, control, communications and intelligence would inevitably benefit the other armies. That was one reason, they said, why the air campaign proceeded slowly. The objective was not to destroy everything the Serbs had in the shortest possible time, but to gradually increase the level of pain until the Serbs said stop.Reuse content