There are some similarities to the 1990-91 Gulf War. Any military response will take time - up to five weeks according to one estimate yesterday.
Bush jun and the old hands advising him will have to work delicately to build a broad international coalition, as his father did against Saddam.
White House officials also predict the result will be the use of overwhelming military force, just as Operation Desert Storm took 100 hours after a five-month build-up.
The challenge is easier on one level, as the United States has broad sympathy and support from around the world, including from Nato, the United Nations Security Council, India and Pakistan and traditional opponents such as Russia and Iran.
But in other ways the job is much harder this time. Iraq's brutal conquest of Kuwait in August 1990 and the threat this posed to world oil supplies demanded an international response.
However, a direct attack on Afghanistan to get at bin Laden's al Qaeda organisation raises difficult questions for America's potential allies, especially in the Middle East.
None of the military options on offer - bombs, missile attacks, invasion and assassination by special forces - looks likely to hurt bin Laden, and the US is still unable to come up with proof that he is responsible for the killings.
There are also suspicions that if the United States succeeds in crushing the Taleban, Bush will be tempted to complete his father's unfinished business by moving in on Saddam Hussein, who has already been speculatively linked with last week's attacks.
Any attempt to extend the coalition's brief in this way would be disastrous for the Muslim countries whose help America needs most, say analysts.
"Arab leaders have a big problem because they are being pulled by two opposite forces," Mustafa Alani, a Middle East specialist at London's Royal Institute for Defence Studies, told the Washington Post.
"On one hand, they want to prove to American public opinion that they are against terrorism.
"But on the other, they are worried about political frustrations inside their own countries and the reactions of their own fundamentalists."
Over the next few days Bush and his team will meet leaders and officials from Russia, Germany, Italy, China, Saudi Arabia, South Korea and Indonesia to drum up support for their much-vaunted coalition against terrorism. This is how it lines up around the world so far.
THE WEST
BRITAIN - Strong support: America's closest ally. Prime Minister Tony Blair, who is heading for Washington today, has pledged to stand "shoulder to shoulder" with Bush and has worked to bring less enthusiastic European states on board. In private Blair is said to be urging caution.
FRANCE - Qualified support: President Jacques Chirac said France would be "totally supportive", but Prime Minister Lionel Jospin said it was up to Paris to decide how to help retaliate and Defence Minister Alain Richard warned against provoking instability. Foreign Minister Hubert Vedrine has also warned against igniting a "clash of civilisations" between the Western and Islamic worlds, and suggested attacking the sources of terrorists' finance, rather than bombing raids which could kill innocent civilians.
GERMANY - Qualified support: Defence Minister Rudolf Scharping suggested in vague terms on Monday that Germany could participate in a military response. Foreign Minister Joschka Fischer earlier expressed caution and said Parliament had the last word.
BELGIUM, ITALY, SPAIN - Strong support: Belgian Foreign Minister Louis Michel said he would send troops to help in US military retaliation. Italy said it would join a military response and was ready to deploy troops and aircraft if asked. Spain offered its air bases for any retaliatory strikes and promised to act "without any reservations".
NATO - Qualified support: It invoked the mutual defence clause for first time in its history, opening the way for a possible collective response. But individual members have expressed reservations and some commentators see the use of the mutual defence clause as a way to rein back the US from acting too hastily.
RUSSIA - Qualified support: President Vladimir Putin has pledged support but urged thorough investigation first. Defence officials have said Moscow will help with intelligence, but military participation is unlikely.
Senior US officials meeting their Russian counterparts overnight in Moscow were expected to ask whether American forces could use airspace in Russia and the former Soviet republics of Tajikistan, Turkmenistan and Uzbekistan, along Afghanistan's northern border. The US could also ask for permission to send ground troops in from the north.
CANADA - Strong support: Foreign Minister John Manley said Canada would "unambiguously" join US military action.
AUSTRALIA - Strong support: Said 295 troops stationed in United States had been given permission to deploy with US forces if needed.
NEW ZEALAND - Support: Has offered to help with intelligence and possibly SAS troops as part of an American-led multinational force. The Opposition has attacked the Government's response so far as reluctant and mean-spirited.
MIDDLE EAST
ISRAEL - Support: Initially Prime Minister Ariel Sharon refused to make concessions to the Palestinians to help US recruit Arab and Muslim nations for its anti-terror alliance. But both sides have now called a truce, Israel withdrawing tanks from Palestinian territory yesterday after President Yasser Arafat called a ceasefire. US sources say Israel is giving vital intelligence support on Islamist militants, but Secretary of State Colin Powell says Israel is not expected to play a role in any military response.
PALESTINIAN TERRITORIES - Qualified support: President Yasser Arafat offered to place all his capabilities at the service of the US and urged Arab states to join a coalition. Arafat is on the defensive after some Palestinians were shown on television welcoming the attacks.
It is also in his interests to keep the peace for now to stop Sharon labelling him as a terrorist.
EGYPT - Opposition: A key US ally in the Middle East, particularly in the 1991 Gulf War, is deeply nervous about reaction from its own Islamic fundamentalists. President Hosni Mubarak said on Monday it was too early to talk of an alliance against "terrorism" and the United States should think twice before taking military action that would kill civilians.
SAUDI ARABIA - Qualified support: Also worried about reaction from fundamentalists at home and one of the key meetings for the US of the next few days. King Fahd has offered support and cooperation but stopped short of spelling out practical help.
Saudi Arabia has denied local newspaper reports that two of the hijackers were sons of a senior Saudi diplomat who served in Washington.
KUWAIT - Strong support: Freed from Iraqi occupation by a US-led coalition in 1991, it has offered all possible help.
TURKEY - Limited support: Has said it is willing to support Washington. Not clear what role it would be asked to play beyond intelligence-gathering. Turkish air bases could be used.
CENTRAL AND SOUTH ASIA
IRAQ - Opposed: A possible target along with Afghanistan. Accused the United States of terrorism, and said the attacks were carried out by American dissidents.
IRAN - Neutral: Potentially one of the biggest shifts in international relations to emerge from this crisis. Iranians, who are Shiite Muslims, detest the Taleban, who are Sunni. Iran has condemned the attacks, but said punishing its neighbour, Afghanistan, might cause a human catastrophe. But senior Iranian officials have reportedly asked Canada to tell the United States (as Tehran has no diplomatic links with Washington) that Iran would not condemn targeted retaliation against those responsible.
Despite the official American view that Iran itself is a sponsor of state terrorism, American officials are now exploring the possibility of greater cooperation, including intelligence. Iran will not be used for overflying or bases.
PAKISTAN - Qualified support: Possibly the most important country in the whole coalition. Pakistan, which is a hotbed of Islamic fundamentalism, has previously backed the Taleban Government and has the power to clamp down on its sources of fuel, food and money.
But under huge pressure from the US (and a promise to lift sanctions imposed after Pakistan's 1998 nuclear tests), President Pervez Musharraf has offered to share potentially valuable intelligence, allow a multinational force within its borders and let American planes fly over its airspace into Afghanistan. Pakistan even sent delegates to Afghanistan to try to persuade the Taleban to hand over bin Laden.
The US assistance is a big domestic gamble by Musharraf, who faces growing opposition from local militant groups.
TAJIKISTAN - Opposed: One of three Islamic former Soviet satellite states north of Afghanistan, with Turkmenistan and Uzbekistan. Against any military action, according to US officials quoted by CNN.
UZBEKISTAN - Support: Has only 160km of frontier with Afghanistan but has showed most enthusiasm to help the Americans. Its air bases at Tashkent and Termez could be useful to the United State. But any final decisions will be made in Moscow.
INDIA - Support: Offered to let US military forces use its facilities if needed. Has a big Muslim minority. Diplomats say Washington is unlikely to need Indian bases.
OTHER COUNTRIES
CHINA - Opposed: Has said it is ready to join the US superpower in fighting "terrorism", but warned that military intervention would only "aggravate terrorism and violence".
JAPAN - Limited support: Struggling to reconcile its constitutional neutrality with loyalty to its key American ally. Criticised in 1991 for supporting US-led war to oust Iraq from Kuwait without committing even a token force to the Gulf.
INDONESIA - Limited support: Megawati Sukarnoputri, president of world's biggest Muslim nation, offered unspecified help. Other top officials have warned the United States not to make Islam a scapegoat.
UNITED NATIONS - Neutral: Security Council has expressed "readiness to take all necessary steps to respond to the terrorist attacks" but this falls far short of formally authorising any military response.
Map: Opposing forces in the war against terror
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