Washington ? President Bush painted an optimistic picture Wednesday night of sweeping democratic change in Iraq that would spread throughout the Arab world and help end the Israeli-Palestinian conflict.

“A new regime in Iraq would serve as a dramatic and inspiring example of freedom for other nations of the region,” Bush said during what aides characterized as a “big picture” speech delivered with a nearly certain war only weeks away.

Though the president has said that he has not yet decided to launch military action against Saddam Hussein, his speech — broadcast live by all major television networks — seemed intended to justify war and focused on activities that would occur after a war.

“The danger posed by Saddam Hussein cannot be ignored or wished away,” he told the American Enterprise Institute for Public Policy Research, a Washington, D.C.-based group that calls itself a nonpartisan think tank. “The danger must be confronted.”

Responding to criticism from many quarters around the nation and world, he said the United States had no desire to seize territory and no designs on Iraqi oil.

“We will remain in Iraq as long as necessary and not a day more,” he said. “America has made and kept this kind of commitment before — in the peace that followed a world war. After defeating enemies, we did not leave behind occupying armies. We left constitutions and parliaments.”

Bush assured the Iraqi people that he has no intention of forcing a U.S.-style government on Iraq.

“That choice belongs to the Iraqi people,” he said. “Yet we will ensure that one brutal dictator is not replaced by another. All Iraqis must have a voice in their new government and all citizens must have their rights protected.”

He also issued a passionate call for peace between Israelis and Palestinians, a process he said would be enhanced by the ouster of Saddam.

President Bush, center, watches as members of the Marine Color Guard leave the stage area before delivering remarks at the American Enterprise Institute annual dinner. Bush on Wednesday night laid out his postwar vision for the Arab world.

The Iraqi leader has been a destabilizing force in Israel and adjacent Palestinian territories, Bush said, and has exacerbated the violence there by financially rewarding the families of Palestinian suicide bombers.

“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 — true leaders who strive for peace,” Bush said.

Bush also served notice that he expects Israel to respond to Palestinian peace overtures by ending Israeli settlements in Palestinian areas. Bush’s surprise endorsement of a longstanding Palestinian demand put him at odds with the Israeli government, which has refused to restrain Israeli settlers.

“As progress is made toward peace, settlement activity in the occupied territories must end,” he said. At the same time, Bush called on Arabs nations to “state clearly (that) they will live in peace with Israel.”

“America will seize every opportunity to pursue the peace. And the end of the present regime in Iraq would create such an opportunity.”

Bush’s 27-minute address came at the end of another active day on nearly every Iraq-related front:

Chief United Nations weapons inspector Hans Blix said Iraq still had not made “a fundamental decision” to disarm, the French intensified their opposition to a prospective invasion, and reports suggested that Mexico, Chile and Angola might be edging toward support of the U.S. position in the U.N. Security Council.

Meanwhile, estimates of the initial cost of a war with Iraq reached $95 billion. That would not include expenses for occupying postwar Iraq, which the Army’s top general told Congress might require several hundred thousand U.S. troops for at least two years.

Still, the president said the United States had a moral responsibility to liberate people ensnared by Saddam’s “nightmare world” of tyranny, and he said it was in the nation’s self-interest to depose him.

“America’s interests in security and America’s belief in liberty both lead in the same direction — to a free and peaceful Iraq,” Bush said.

“The world has a clear interest in the spread of democratic values because stable and free nations do not breed the ideologies of murder. They encourage the peaceful pursuit of a better life.”

He warned that the effort will not be easy. “Americans do not turn away from duties because they are hard,” he said.

But he defended his policy as necessary and likely to produce more good than harm, largely because the introduction of a democratic government in Iraq could inspire beneficial change throughout the Middle East.

His optimistic outlook is far from unanimously shared by Middle East experts.

Skeptics contend that a U.S. invasion of Iraq could just as easily lead to disaster, with thousands of American deaths, a new wave of terrorism and increased instability throughout the region.

Iraq itself could fragment, with Kurds in the north and Shiite Muslims in the south seeking to create independent states. Instead of easing Israeli-Palestinian tensions, heightened regional pressure could trigger escalating violence on both sides.

“You’re opening up a box and no one knows what’s going to come out of the box,” said Geoffrey Aronson, the director of research at the Foundation for Middle East Peace, an organization sympathetic to the Palestinian cause. “Nobody has a clue, and anybody who says they do doesn’t know what they’re talking about.”

In other developments:

l A senior Defense Department official said the United States expected Iraq to use “human shields” — possibly including volunteer peace activists from around the world — to help defend Baghdad and other cities.

“This is a well-organized, centrally managed effort, and its objectives are patently clear,” said the official, who requested anonymity. “Preserve Iraq’s military capabilities at any price.”

Defense Secretary Donald Rumsfeld said that would be a war crime.

l The United States and Britain appeared to be making progress in their campaign to line up support on the 15-member Security Council for a new resolution that would clear the way to war.

Mexico, which originally opposed the measure, reportedly told its diplomats to begin shifting closer to the U.S. position, though Mexican diplomats at the United Nations refused to discuss the reports. The Mexican government said late Wednesday that it “continues to be independent and autonomous.”

Chilean President Ricardo Lagos also seemed to be swinging toward the U.S. position. “If at the end the (U.N.) accords are not respected, then force may be needed,” Lagos said during a speech in the city of Ovalle.

Lagos has been in frequent contact with Mexican President Vicente Fox. Bush spoke with both Latin leaders over the weekend.

In addition, Angola’s ambassador to the United Nations said his nation was seeking an accommodation with the United States.

l In Qatar, British Defense Minister Geoff Hoon predicted that the U.S.-British-Spanish resolution would win the required nine votes when it comes up for consideration late next week.

l French Prime Minister Jean-Pierre Raffarin reiterated his nation’s opposition to a military strike before “all chances for a peaceful solution” are explored. He said war now would divide the international community and “be perceived as precipitous and illegitimate.”

l In London, Parliament approved a motion giving Saddam a “final opportunity” to disarm, but more than one-quarter of Prime Minister Tony Blair’s own Labor Party members voted for an antiwar amendment.

l Under intense U.S. pressure and despite considerable internal dissent, the Turkish Parliament appeared poised to grant final approval Thursday to a deal that would allow 62,000 U.S. troops to use Turkish bases as jumping-off points for a possible attack across Iraq’s northern border.

A final deal had been delayed by differences over the size of a U.S. aid package and the role Turkish troops would play in Kurdish-controlled northern Iraq.

In a related development, an AWACS early warning aircraft, Patriot defense missiles and other military hardware began arriving in Turkey to help protect that nation from a retaliatory strike by Iraq.