Republican Sen. Richard G. Lugar (search) on Saturday said the United States isn't doing enough to stave off terrorism and criticized President Bush (search) for failing to offer solid plans for Iraq's future.

Lugar, chairman of the Senate Foreign Relations Committee (search), said the nation must prevent terrorism from taking root around the world by "repairing and building alliances," increasing trade, supporting democracy, addressing regional conflicts and controlling weapons of mass destruction.

Unless the country commits itself to such measures, "we are likely to experience acts of catastrophic terrorism that would undermine our economy, damage our society and kill hundreds of thousands, if not millions, of people," the Indiana senator said during an appearance at the Fletcher School at Tufts University (search).

Lugar said military might alone isn't enough to eradicate terrorism.

"To win the war against terrorism, the United States must assign U.S. economic and diplomatic capabilities the same strategic priority that we assign to military capabilities," he said.

He later added, "Military action is necessary to defeat serious and immediate threats to our national security. But the war on terrorism will not be won through attrition — particularly since military action will often breed more terrorists and more resentment of the United States."

Lugar, who was awarded the Dean's Medal for distinguished service in international affairs, said it's still unclear how much control the Iraqi people will have over their nation's security when power is transferred to them June 30.

"I am very hopeful that the president and his administration will articulate precisely what is going to happen as much as they can, day by day, as opposed to a generalization," he said.

It's not the first time that Lugar has criticized Bush, a fellow Republican. In 2003, Lugar and Sen. Joseph Biden, the committee's top Democrat, warned that the Bush administration had not given enough consideration to what would happen in Iraq after the fighting ended.

Also Saturday, Lugar blamed the Bush and Clinton administrations for not adequately funding the foreign affairs budget, noting that the military's budget is more than 13 times what the nation spends for diplomacy.