Washington -- The destruction of Saddam Hussein's regime would free the Iraqi people from a brutal dictator, encourage the gathering forces of political reform in the Middle East and facilitate an Israeli-Palestinian peace settlement, President George W. Bush said last night.

In a broad defense of his Iraqi policy, Bush argued that the need to protect Americans from the threat of Hussein's weapons of mass destruction dovetailed with a long-standing U.S. commitment to promote a freer and more stable world.

"America's interests in security and America's belief in liberty both lead in the same direction: to a free and peaceful Iraq," the president said in a speech to the annual dinner of the American Enterprise Institute, a conservative Washington think tank.

In setting forth such sweeping strategic justifications for his policy of confronting Hussein by force if necessary, Bush's speech seemed addressed as much to critics in the Middle East and Europe as to the American public. Critics have argued that a U.S.-led war would bring fresh misery to Iraqis, destabilize moderate Arab regimes and spread Islamic radicalism and anti- American sentiment in the region.

By arguing the opposite case, Bush associated himself with the thinking of an influential group of neoconservatives in his administration who have long argued that Hussein's ouster would provide a powerful boost to the embattled forces of moderation and reform within the Arab and Muslim worlds.

"A liberated Iraq can show the power of freedom to transform that vital region by bringing hope and progress into the lives of millions," he said. "And there are hopeful signs of a desire for freedom in the Middle East ... From Morocco to Bahrain and beyond, nations are taking genuine steps toward political reform. A new regime in Iraq would serve as a dramatic and inspiring example of freedom for other nations in the region."

Bush said American forces would enter Iraq not as conquerors but liberators, bearing food and medicine and empowering Iraqis to determine their new form of government and leaders. He said the duration of the U.S. presence in Iraq, which some officials have said could last as long as two years, would be "as long as necessary, and not a day more."

And he said any difficulties encountered in creating a stable and unified Iraq are "no excuse to leave the Iraqi regime's torture chambers and poison labs in operation. Any future the Iraqi people choose for themselves will be better than the nightmare world that Saddam Hussein has chosen for them."

Turning to the Israeli-Palestinian conflict, an issue several European leaders have recently urged him to address as he moves toward war in Iraq, Bush broke no new ground. He restated his formula that Israel must eventually accept a Palestinian state and end "settlement activity" in the occupied territories - but only after Palestinians reform their political institutions and end terror attacks on Israelis.

However, Bush sought to link the two issues by arguing that Hussein's ouster could "begin a new stage for Middle Eastern peace and set in motion progress towards a truly democratic Palestinian state" that renounces terror tactics.

"The passing of Saddam Hussein's regime will deprive terrorist networks of a wealthy patron that pays for terrorist training and offers rewards to families of suicide bombers," he said. "And other regimes will be given a clear warning that support for terror will not be tolerated. Without this outside support for terrorism, Palestinians who are working for reform and long for democracy will be in a better position to choose new leaders."

Finally, answering critics who argue that his willingness to wage war threatens international institutions, Bush argued that he was in fact trying to strengthen them.

"High-minded pronouncements against proliferation mean little unless the strongest nations are willing to stand behind them and use force if necessary," he said. "The threat to peace does not come from those who seek to enforce the just demands of the civilized world. The threat to peace comes from those who flout those demands."