Are these the detailed battle plans for the most heavily trailed military attack in modern history?

The plans are on the President's desk. The variants are several, and no final, irrevocable decision has been taken by George Bush. But there is every sign that Washington wants the seemingly inevitable Gulf War II to topple Saddam Hussein to be a nimbler, more focused and even fiercer enterprise than the campaign waged by Mr Bush's father to drive him from Kuwait in 1991.

A spate of news stories in Washington at the weekend provided yet more details about what is surely the most heavily trailed, unprovoked military attack by one nation on another in modern history. "I am not saying there is no plan on the President's desk," Ari Fleischer, the White House spokesman declared, confirming a report in The New York Times that General Tommy Franks, head of Central Command and the man who would run the campaign, had submitted to Mr Bush a detailed set of options for war.

Yesterday, The Washington Post followed up with a blend of leaks and highly informed speculation, suggesting that the war would target President Saddam's hometown stronghold of Tikrit, held to be the geographical and political intersection between the Iraqi leader himself, his most devoted and ruthless followers, and the chemical and biological weapons Iraq is said to possess.

Quite why so much information is emerging now, four months in all probability before the shooting starts, is a separate tale. Part of the explanation is the competitive rivalry between the Post and the Times.

But leaks of military plans do not happen by accident. Donald Rumsfeld, the Defence Secretary, may fulminate about them in public, with the straightest of faces. But they serve the administration's purpose of keeping the heat on President Saddam, convincing him that unless he bows to Washington's will, no amount of prevarication or finessing the Security Council will prevent the US from acting, even on its own. The administration hopes that a congressional resolution authorising the use of force can be adopted swiftly, despite Democratic objections.

In the meantime, a picture of a possible military campaign steadily emerges.

Unlike the 1991 Gulf War, which was preceded by a six-month build-up, Gulf War II would be much more intense, aimed at decapitating the regime, neutralising Iraq's deadliest weaponry with as little "collateral damage" to the civilian population as possible.

It would involve less than the 250,000 troops first mooted, probably no more than 100,000, possibly as few as 50,000. It would be preceded by an aerial assault far fiercer than those in Kosovo or Afghanistan, destroying Iraqi command and control structures, presidential sites and bases of the Republican Guard, the most loyal component of Iraq's armed forces.

Simultaneously commando units would go after the Scud missiles which a cornered President Saddam might unleash against Israel, in the hope of triggering a wider Middle East conflagration.

That risk has only grown after statements from Ariel Sharon's ministers that in contrast to its restraint when Iraq fired Scuds in 1991, Israel this time would retaliate in kind. That in turn could provoke the wider Arab-Israeli war feared by the dwindling band of politicians, analysts and commentators here who still urge caution on Mr Bush.

Senator Joseph Biden, the chairman of the US Senate Foreign Relations Committee, warned on US television yesterday that if Israel responded to an attack, no Muslim nation, including such critical allies as Saudi Arabia and Turkey, could support the American effort against Iraq, even behind the scenes. "And you would find probably every embassy in the Middle East burnt to the ground before it went too far," he added.

To minimise the danger, speed is vital. All along, Mr Rumsfeld has demanded that the military planners come up with a more unconventional and "creative" blueprint, that would permit the US to achieve tactical, if not strategic, surprise in the attack.

The idea which seems to have prevailed, is something close to the "inside-out" concept which surfaced in the summer, calling for a blitzkrieg against a few key targets – first among them Tikrit and Baghdad. The onslaught, it is calculated, would provoke the implosion of the regime and the swift collapse of resistance elsewhere in Iraq.

The US build-up could not pass entirely unobserved by the enemy. But The Washington Post suggested any attack would be spearheaded by three divisions, two of them heavily armoured, one a more mobile US Marines unit, totalling about 50,000 men. A similar-sized force would be held in reserve, to be rushed in as reinforcement if needed.

Other factors too work for surprise. A number of US troops have been moved quietly to the Gulf region, others are joining them for "exercises". US strength there may already be 20,000 men, some observers believe. Moreover large quantities of equipment have long been pre-positioned around Iraq. And for all their public opposition to an attack on Iraq, Jordan and conceivably even Saudi Arabia would turn a blind eye to low-profile commando operations launched from their territories to take out key targets and hunt Scud missiles.

The finishing touches are now being put to these plans even as, in New York, Washington and London, US and British officials pursue the parallel diplomatic track, trying to persuade Russia, France and China not to block a tough new Security Council resolution demanding unfettered access for UN weapons inspectors and setting a deadline for Iraq's compliance.

Whether that resolution, or a subsequent one, would contain an explicit warning that the alternative is force, is far from clear. In truth, however, debate is quickly becoming superfluous. President Saddam on Saturday declared he would reject any new UN resolution, and his aides hint ominously that the infamous presidential palaces and other "sovereign sites" will remain covered by existing agreements which effectively rule out surprise inspections.

Mr Bush meanwhile insists the US will go it alone, if necessary, to enforce total compliance. His Secretary of State, Colin Powell, warned last week that if UN weapons inspectors were moved back to Iraq under the existing agreements with Baghdad, the US "would find ways to thwart that".

Room for compromise has all but vanished. The assumption is that Mr Bush wants the decks cleared for action by February, or March at the latest, when cooler weather makes it easier for troops to fight in the cumbersome gear protecting them against germ and chemical weapons.

But even though Iraq's forces are weaker than in 1991, and those of the US even better armed today, General Franks knows that few military plans survive the start of the fighting. "We are prepared to do whatever we are asked to do," he said yesterday after visiting US servicemen in Kuwait.

But the general has no more idea than anyone else whether President Saddam already has his biological and chemical weapons ready for use (possibly even pre-emptively, to use the vogue phrase). He cannot judge how hard Saddam's crack troops will fight, or whether ordinary Iraqis really would embrace the US invaders as liberators, as hawks here believe.

If they do, then the fighting, according to planners quoted by The Washington Post, could be over in a week. If not, the US could find itself embroiled in a protracted and bloody battle for Baghdad, damned in the court of world opinion, helpless as whatever grand design it has for the "day after," post-President Saddam Iraq crumbles. All the plans and all the leaks in the world cannot cover such contingencies.