Washington ? War with Iraq appeared all but inevitable Wednesday as the Bush administration launched the “final phase” of consultations with hesitant allies and political foes, and United Nations members planned the equivalent of a war council.

With U.S. troops streaming toward the Persian Gulf, President Bush said:

“History has called the United States into action, and we will not let history down.”

A U.S.-led war on Iraq could start as early as the beginning of March, several senior administration officials said, and the White House flashed war signals on many public fronts.

“It certainly feels around here as if the preposition has changed from ‘if’ to ‘when,”‘ one State Department official, speaking on condition of anonymity, said about the widespread feeling that Bush has chosen war. “It certainly feels like there’s a green light.”

Speaking one day after his State of the Union address, Bush ratcheted up his rhetoric about the threat posed by Iraqi dictator Saddam Hussein.

“He is a danger not only to countries in the region, but, as I explained last night, because of al-Qaida connections, because of his history, he’s a danger to the American people, and we’ve got to deal with him,” the president said during a speech in Grand Rapids, Mich. “We’ve got to deal with him before it is too late.”

Other top U.S. officials said that before acting alone or with a few allies, they would wait weeks — but not months — for the United Nations to put teeth into its threat of “serious consequences” for Saddam if he fails to disarm peacefully.

At the Pentagon, Defense Secretary Donald Rumsfeld made his strongest effort yet to justify pre-emptive military action on moral grounds, even while conceding that Americans traditionally have believed that “unless attacked, one does not attack.”

“The question, though, is, in the 21st century — with biological weapons, for example, that could kill hundreds of thousands of people — what does one do?” he asked. “Does one wait until they’re attacked?”

Meanwhile, Secretary of State Colin Powell again invited Saddam to end the crisis quietly by accepting life in exile. “We would help try to find a place for him to go,” Powell said.

Few experts think Saddam would leave power voluntarily, but the increased talk of it was another signal that Washington was moving closer to invading.

In Baghdad, Saddam appeared on television to express his defiance. “We will absorb the momentum of the attack, destroy it and defeat it,” he said.

The White House confirmed that Powell, in a moment of high drama next Wednesday, will give the United Nations evidence that Iraq continues to conceal and develop weapons of mass destruction. The foreign ministers of many U.N. Security Council nations are expected to attend the session, in effect creating an international war council.

Powell also is expected to present evidence concerning Iraqi ties with terrorists and to detail alleged Iraqi efforts to undermine and manipulate the U.N. inspections process.

Powell, who met Wednesday with Pakistan’s foreign minister at the State Department, said he would offer “new information” that was “not relevant to the inspectors’ work,” but nonetheless illuminated Iraq’s banned weapons programs.

Additional information, Powell said, “will be an expansion” of past U.S. presentations. Others described the data as more of a mosaic than a single “smoking gun.”