The capture of Saddam Hussein by about 600 troops from the 4th Infantry Division and Special Operations units Saturday evening was the long-awaited break in a war that threatened to ensnare the United States in a costly spiral of lost lives and lost confidence.

Saddam Hussein was the prime goal of the war. He was the reason for the risk and the casualties, the alienation of allies, the expenditure of billions of tax dollars. His capture likely will not end the guerilla attacks nor will it make much difference in global terrorism, but his arrest was a crucial step toward reassuring the Iraqi people that change really has arrived in their country, that the U.S. forces are capable of ending this war successfully, that hope is a reasonable emotion.

Speaking yesterday, President George Bush said, “In the history of Iraq, a dark and painful era is over. A hopeful day has arrived. All Iraqis can now come together and reject violence and build a new Iraq. … Now the former dictator of Iraq will face the justice he denied to millions.”

President Bush, like the U.S. administrator in Iraq, L. Paul Bremer, was careful to say the fighting isn’t over. Indeed, if Mr. Hussein was as disheveled as he appeared in a video taken after his capture, he may not have been masterminding any kind of counterattack but running for his life for some time. That suggests the attacks can continue without him, although the Iraqi forces still fighting will have to wonder what they hope to get now by risking their lives.

President Bush’s comment above, about justice, was very important. What happens to Saddam Hussein next can accomplish much good for the U.S. mission by bringing a sense of power to the Iraqi people and fairness to its new governing institutions. U.S. officials said they still haven’t decided what to do with Mr. Hussein. It is understandable that they would not want to commit to any course immediately. But just last week Iraq’s interim government established a special tribunal to try him in his absence and to try high-ranking members of his cabinet for genocide, war crimes and crimes against humanity. To place Mr. Hussein before such a tribunal would demonstrate that not only is he no longer able to regain power but that his brutal system of governing has been similarly demolished.

The arrest was much more than symbolic but it was important that way, too. Iraqis have been celebrating since the news spread, joyous in a way they dared not be last spring, and U.S. and allied forces got the sort of morale boost they needed to help them through an extraordinarily difficult mission. As Mr. Bremer observed yesterday, “The tyrant is now a prisoner.”