WASHINGTON (REUTERS) — President Bush, in a somber State of the Union speech, vowed Tuesday to use the full force of the U.S. military against Iraq if needed and warned U.S. troops that “some crucial hours may lie ahead” as he braced wary Americans for a possible war.

“For the brave Americans who bear the risk, no victory is free from sorrow. This nation fights reluctantly because we know the cost, and we dread the days of mourning that always come,” Bush told a national television audience from the chamber of the House of Representatives, which was brimming with lawmakers, Cabinet secretaries and other dignitaries.

The hour-long speech was critical to Bush’s attempt to marshal backing for possible war. There is a growing anxiety among Americans about going to war with Iraq, and U.N. Security Council members have urged the United States to use caution and give U.N. weapons inspections more time.

At the same time, he sought to reassure Americans jittery about a weak U.S. economy he said was still shaken by the aftermath of a recession, the Sept. 11, 2001, attacks, corporate scandals and stock-market declines. He promoted his $674 billion tax cut plan as a necessary balm.

Bush sketched his portrait of an Iraq needing the removal of Saddam Hussein with little new evidence of an imminent threat and a broad reiteration of previous charges.

But Bush said Secretary of State Colin Powell was ready to present evidence of Saddam’s weapons program to the United Nations next week and responded to critics who have said the threat from Iraq is not imminent.

“Some have said that we must not act until the threat is imminent,” Bush said. “Since when have terrorists and tyrants announced their intentions, politely putting us on notice before they strike?”

To U.S. forces in the Gulf region expected to be ready for combat next month, Bush said, “Many of you are assembling in and near the Middle East, and some crucial hours may lie ahead. In those hours, the success of our cause will depend on you.”

He added, “If war is forced upon us, we will fight with the full force and might of the United States military — and we will prevail.” Sending Americans into battle, he said, is “the most profound decision a president can make.”

Powell ready to provide intelligence

To try to convince doubting allies, Bush called on the U.N. Security Council to convene Feb. 5 to hear Powell present information and intelligence about Iraq’s suspected weapons of mass destruction programs.

Sen. Edward Kennedy, a Massachusetts Democrat, said he planned to introduce a resolution in the Senate calling on Bush to present Congress with “convincing evidence of an imminent threat before we send troops to war with Iraq.”

U.N. arms inspectors have not found any major evidence of the weapons of mass destruction Iraq denies having or trying to obtain.

Democrats also urged Bush to seek international backing.

“We must convince the world that Saddam Hussein is not America’s problem alone — he’s the world’s problem,” Washington state Gov. Gary Locke said in the official Democratic response to Bush’s speech.

Bush made clear America was prepared to act to disarm Iraq with or without U.N. backing.

“We will consult, but let there be no misunderstanding: If Saddam Hussein does not fully disarm, for the safety of our people, and for the peace of the world, we will lead a coalition to disarm him,” he said.

He said evidence from intelligence sources, secret communications and statements from people now in custody reveal that Iraqi President Saddam Hussein “aids and protects terrorists,” including members of al Qaeda, and could provide them with banned weapons of mass destruction.

The lack of a clear link between Saddam and the Sept. 11 attacks has hampered the U.S. case that Iraq is part of the war on terrorism. In his speech, Bush provided no fresh evidence of that link.

But he said Saddam has failed to account for a large amount of deadly chemical and biological agents even three months after the U.N. Security Council gave him a final chance to disarm.

“He has shown instead his utter contempt for the United Nations and for the opinion of the world,” Bush said.

Presidential catchall

A president’s State of the Union address is often a catchall for his favorite programs and a platform for new initiatives. Bush’s was no exception, even as most of his national and world audience concentrated on his Iraq comments.

He did propose a five-year $15 billion initiative to fight AIDS in Africa and the Caribbean, $6 billion to fund Project Bioshield to quickly make available vaccines and treatments for bioterrorism attacks, and a push to provide some prescription drug benefits for the elderly under Medicare.

As for his “axis of evil” statement from last year lumping Iraq together with North Korea and Iran, Bush did not repeat that phrase.

Instead he said, “Different threats require different strategies,” to explain why he was seeking a diplomatic approach to North Korea’s nuclear program and encouraging a democratic movement in Iran.

“The North Korean regime is using its nuclear program to incite fear and seek concessions. America and the world will not be blackmailed,” he said.

As a measure to avoid a repeat of the Sept. 11 attacks, Bush said he was instructing the heads of the FBI, CIA, Department of Homeland Security and the Defense Department to develop a “terrorist threat integration center” to merge and analyze all threat information in a single location.

And as a reminder of Sept. 11, one seat in First Lady Laura Bush’s VIP seating box for the speech was to remain empty.

Bush sought to assure Americans his $674 billion economic plan holds the key to restoring growth in the lackluster U.S. economy, amid a 6 percent unemployment rate, shaken investor confidence and a jobless recovery.

He said his economic plan, which includes eliminating taxes investors pay on dividends and speeding up tax rate cuts, will help give a boost to the U.S. economy.

But a possible 2004 challenger, Democratic Sen. John Edwards of North Carolina, said Bush “just doesn’t get it.”

“Giving tax cuts to the very wealthiest Americans should not take priority over the real economic, health-care and security concerns facing regular people,” Edwards said.