At this stage of the Gulf War, five weeks after the first air attacks, it was possible to guess at Gen Schwarzkopf's options.
Clearly, the allied air forces had rendered Iraqi army reconnaissance blind and unable to manoeuvre.
So the main part of his attack plan, a powerful left hook, was predictable. The decision not to use the thousands of US Marines for a landing was more surprising. We know now that the Iraqis guessed wrongly and prepared for that. Gen Schwarzkopf did not oblige.
Gen Clark will also try to surprise the Yugoslavs. Surprise is a principle of war which "can decisively shift the balance of combat power" as the US Field Manual says (or used to).
He will have air supremacy, at least at levels above 10,000 feet. Below that, attacking aircraft will be endangered by surviving short-range surface-to-air missiles, and what used to be called anti-aircraft (AA), now Air Defence (AD), guns.
The Yugoslav army had 1,850 AD guns when the war started. Some must now be unusable. NATO probably hopes to take out most of these guns and missile-launchers before ground troops go into Kosovo. Essentially, the air and ground defences should be so "softened up" that there will be little coherent ground resistance.
From the Desert Storm scenario, Phase I in Kosovo might be "to command the air" (by destroying air defence systems) and to "degrade" military and civil power centres, including economic targets. "Isolating the battlefield" might be Phase II; difficult with Kosovo, as long borders give the Serbs easy access. Phase III, "prepare the battlefield" for ground invasion. Phase IV, ground invasion against a weakened force cut off from supplies and reinforcements.
The difficulties are obvious. Phase I is still in progress. Some elements of Phase II continue - attacks on ministries, barracks, bridges and transport - as well as elements of Phase III, destruction of airfields in Kosovo and attacks on Yugoslav troops.
Phase IV, the ground invasion, still seems far ahead. August is mentioned for completing troop assembly but this may be disinformation.
Kosovo is a small area. Sophisticated mines are being sown on the borders. So mine clearance will be first priority.
Thessalonika, in Greece, provides the best port for troops and logistics. From there a motorway runs through Greece and Macedonia to Kosovo, but neither Greece nor Macedonia has agreed to being used.
A deception plan based on a build-up of troops in Hungary to threaten Belgrade and draw off Yugoslav forces from Kosovo is militarily possible but difficult politically. An approach via the poorly equipped Albanian port of Durres and bad mountain roads is politically feasible (Albania has no serious objections) but militarily horrendous. Montenegro is similar militarily but more difficult politically.
At this stage good diplomacy is vital. There are agreements to be reached, favours promised, arms twisted gently or otherwise, well away from the battlefields. The states adjoining Kosovo know they will have to live with Serbia after NATO troops are gone. They can set a high price.
A political decision is necessary about the Kosovo Liberation Army. They could be useful to NATO troops in Kosovo. They know the ground. They could help against guerrilla tactics by the Yugoslav army. One can see why NATO's fervently preferred options are a "permitted" entry into Kosovo, a forceful entry after the severe degradation of the Serb army there, or a combination of the two.