It is a war against thousands of enemies, on dozens of battlefronts, fought with weapons both loud and silent.

Bombs, spies, commandoes. Sanctions, financial controls, Internet surveillance. All could be unleashed as Washington counters Tuesday's devastating attacks with a worldwide assault on terrorism.

The chief target under consideration for a military strike is Afghanistan, the refuge of accused terrorist mastermind Osama bin Laden and thousands of militant anti-American Muslims loyal to him.

But the U.S. arsenal, military and diplomatic, will also be aimed at other countries judged lacking in their efforts to clamp down on terrorism.

Americans and their allies will be asked to accept tightened security, and possibly curbs on individual freedom, to make it easier to track Islamist militants.

And there will be few of the customary qualms about sending members of the U.S. armed forces into danger. "The task of vanquishing these terrible enemies . . . falls to you," Defense Secretary Donald Rumsfeld told them.

Strong, sober voices say military methods will be ineffective against mass terror.

Wars, they say, are fought against people who want to conquer territory or take over a government -- not people who set out to kill themselves in acts of pure revenge. Wars make detective work harder, not easier.

But in the United States, the logic of war prevails.

"These are not criminals," independent military analyst William Arkin said. "They're not people out for personal gain. These are people who have political objectives. Ergo, it's war."

Besides a strike against Afghanistan, U.S. officials said options include sending elite special forces on undercover operations abroad and long-range bomb strikes.

Although there was clearly support among the U.S. public for an immediate show of force, officials stressed that the campaign would take some time. "This is not going to be a short program," Navy Secretary Gordon England said.

Former president Bill Clinton miscalculated when he sought to punish Mr. bin Laden and governments friendly to him.

In 1998, retaliating for bomb attacks on two U.S. embassies in Africa, he sent cruise missiles slamming into a factory in Khartoum that allegedly produced nerve-gas chemicals for Mr. bin Laden. The Sudanese government said it was producing medicine.

The United States also launched cruise missiles against reputed terrorist camps in Afghanistan. But Mr. bin Laden escaped unscathed.

Several analysts said the administration of President George W. Bush was proceeding more cautiously -- looking for convincing evidence of Mr. bin Laden's involvement in Tuesday's attacks and lining up diplomatic support.

"All of a sudden the Bush administration has woken up to the usefulness of allies and partners," said David Malone of the International Peace Academy in New York.

Pakistan, a strong supporter of Afghanistan's Taliban regime, is a key target of the diplomatic assault.

If it resists U.S. pressure to lean on the Taliban to turn over Mr. bin Laden, it could face economic sanctions. But Dr. Malone said sanctions work too slowly to be "appropriate to the current level of outrage."

U.S. Secretary of State Colin Powell said yesterday he was gratified that Syria -- one of seven nations on a U.S. list of terrorism sponsors -- had agreed to co-operate. Mr. Bush also won unprecedented support from NATO this week for military action.

Mr. bin Laden's al-Qaeda (The Base) network is believed to operate in a decentralized fashion, with members in several countries in various stages of planning attacks.