Wooing Pakistan has not been easy. But of all the regional powers it was the most crucial strategically and politically in the battle that is coming. And yet its membership of the US's informal alliance is both a strength and, importantly, a constraint, a price that some in the US would prefer not to pay.
The US Secretary of State, Colin Powell, had reiterated the Bush formula to the country's leader Gen Pervez Musharraf - you have to decide whether you are with us or against us.
Powell's deputy and best friend, Richard Armitage, was even blunter in a session with Mahmoud Ahmed, the head of Pakistani intelligence. When Ahmed begun to demur that "much history" was involved in any Pakistani decision to go after Osama bin Laden, Armitage leapt up from his desk, growling, "History starts today".
Convinced that the US can succeed in this new form of war only if it wins hearts and minds in the world community, and particularly in the Middle East, the building of the alliance is for Powell the central strategic imperative, one that must, if necessary, take precedence over dreams of a great war against all the harbourers of terrorism.
To date Powell, no pacifist, it should be emphasised, has had his way. President Bush has listened and been patient. But there has been a growing clamour from within and around the Administration, and from the ranks of neo-conservative columnists close to the Administration's hard right, against what is seen as Powell's appeasing tactics. Many have never forgiven him for arguing that the Gulf War should end with the retaking of Kuwait and regard the overthrow of Saddam Hussein as unfinished business. Business that should be finished now.
In essence the choices are stark, as John Diamond of the Chicago Tribune puts it, "one involving making as many friends as possible, the other destroying as many enemies as possible".
Or, put another way, the choice is between a commitment to multilateralism as a policy and method, or to unilateralism, the raw assertion of US power.
Within the Administration Paul Wolfowitz, the deputy Secretary of Defence, has been the most vocal opponent of the Powell desire to limit the campaign initially to Afghanistan. Long an advocate of overthrowing Saddam, he has said publicly the US should be "ending states who sponsor terrorism".
His comment brought an icy response from Powell four days later: "I think ending terrorism is where I would like to leave it, and let Mr Wolfowitz speak for himself," he said.
But the latter is not on his own. His boss, Don Rumsfeld, the Vice-President, Dick Cheney, and the latter's chief of staff, Lewis Libby, are all seen as hawks on the issue.
Within days of the attack, a meeting of the Pentagon's Defence Policy Board (DPB), a prestigious advisory group dominated by neo-conservatives, was reportedly overwhelmingly in favour of immediately expanding the military options aimed at Iraq that were already under active consideration.
"This isn't the time to cut clever political deals that result in halfway measures in the war against terrorism," said Kim Holmes, a member of the DPB and of the right-wing Heritage Foundation, a Washington public policy centre. "If the price is too high, the President should tell would-be allies that Americans will get the job done without them."
Holmes said the administration was in danger of building "an unwieldy coalition of military forces that gives everybody a seat at the decision table."
Another shot across the Powell bow has come in an "Open Letter" co-signed by 41 foreign-policy scholars, including the chairman of the DPB, Richard Perle, another of its members, William Bennett, the former UN ambassador Jeanne Kirkpatrick, the publisher of the Weekly Standard, William Kristol, and the editor in chief of the liberal New Republic, Martin Peretz, essentially the entire neo-conservative establishment.
They say that to retain their support Bush must target Hezbollah for destruction, and retaliate against Syria and Iran if they refuse to cut all ties to the group. He must also move militarily to overthrow Iraq's Saddam Hussein. Failure to attack Iraq, they warn "will constitute an early and perhaps decisive surrender in the war on international terrorism".
Bennett wants Congress to declare war on "militant Islam" and "overwhelming force" used on state sponsors of terror such as Lebanon, Libya, Syria, Iraq, Iran and even China.
In the media the pundits, defence experts, and the likes of Rush Limbaugh, have let rip, accusing Powell not merely of being misguided, but disloyal to the President and suggesting cowardice - "When advocates of merely minor objectives are praised as 'cooler heads', the pertinent attribute may be cold feet," columnist George Will sneered last week.
Kristol, who also took pot shots at Powell during the China spy-plane crisis, reminded Washington Post readers of Powell's Gulf War record and claimed that "Since his speech to Congress last Thursday, virtually every major political figure has gone out of his way to support the President. Except for his Secretary of State. On the Sunday talk shows, Colin Powell revised or modified many of his boss's remarks.
"What's going on here? Powell is desperate to focus our effort on bin Laden's al-Qaeda. Holding the Taliban responsible would raise questions about the role of governments in supporting terror, and might suggest a general policy of rΘgime change where possible. Powell is hostile to any such policy, in part because such a policy might require a broader military engagement . . .
Or take Ann Coulter of the National Review: "We know who the homicidal maniacs are . . . We should invade their countries, kill their leaders and convert them to Christianity."
The Wall Street Journal editorialised bluntly. "Mark us down for supporting a major military strike, not just in Afghanistan in pursuit of Osama bin Laden, but if need be against terrorist enclaves in a host of countries."
"We recognise that taking the war to Iraq won't be easy, but the prospect that he might use nuclear, biological or chemical weapons in the future should concentrate the national mind."
For the neo-conservative right the tragedy of September 11th has become an opportunity to settle old scores and reassert America's global power, to shake off the wimpish centrists whose compromising is seen as jeopardising their great Reaganite dream of finally defeating the renascent evil empire.
As Ireland's Minister for Foreign Affairs, Brian Cowen, admitted on his way through here this week, America's European allies, who have lived with and absorbed the complexity of the challenge of reconciling historic enemies, find Powell reassuring as they prepare for the inevitability of military conflict. They look over his shoulder with some unease.
