Vice President Dick Cheney, pressing the Bush administration's case for toppling Iraqi leader Saddam Hussein, said Sunday Saddam is aggressively seeking nuclear and biological weapons.
"The United States may well become the target" of an attack, Cheney said.
Cheney said that the United States is justified in striking any country it believes is planning an attack against America, applying the Bush administration's new foreign policy doctrine on pre-emptive military action to Iraq.
Cheney and top administration officials took to the Sunday talk shows as part of President Bush's effort to convince the public, Congress and other countries that action against Saddam is urgently needed. The officials cited the Sept. 11 attacks in making the case that the world cannot wait to find out whether the Iraqi president has weapons of mass destruction.
"The problem here is that there will always be some uncertainty about how quickly he can acquire nuclear weapons. But we don't want the smoking gun to be a mushroom cloud," national security adviser Condoleezza Rice said in a televised interview.
"How long are we going to wait to deal with what is clearly a gathering threat against the United States, against our allies and against his own region?"
Added Defense Secretary Donald H. Rumsfeld on CBS' Face the Nation: "Imagine, a September 11 with weapons of mass destruction. It's not 3,000; it's tens of thousands of innocent men, women and children,"
Cheney, citing unspecified intelligence gathered over the past 12 months to 14 months, said on NBC's Meet the Press Saddam has the technical expertise and designs for a nuclear weapon, and has been seeking a type of aluminum tube needed to enrich uranium for a weapon. The tubes have been intercepted through one known channel, Cheney said.
"We know we have a part of the picture and that part of the picture tells us that he is in fact actively and aggressively seeking to acquire nuclear weapons," Cheney said.
Cheney said he did not know for sure whether Saddam already has a nuclear weapon. Gen. Richard Myers, chairman of the Joint Chiefs of Staff, said he did not think so.
Bush will address the United Nations on Thursday to build his case for action against Iraq. But Secretary of State Colin Powell said whatever the United Nations decides, Bush will reserve the right to go it alone against Iraq.
"The president will retain all of his authority and options to act in a way that may be appropriate for us to act unilaterally to defend ourselves," Powell said on Fox News Sunday.
Bush outlined a new doctrine in June warning he will take "pre-emptive action, when necessary, to defend our liberty and to defend our lives." He mentioned no specific nations at the time. On Sunday, Cheney pointed a finger directly at Iraq.
Critics, some of them in countries allied with the United States, have questioned whether military action to achieve the U.S. government's goal of overthrowing Saddam Hussein from power is legal under international law.
Asked about the criticism, Cheney said in the case of Iraq, such action is justified.
"If we have reason to believe someone is preparing an attack against the U.S., has developed that capability, harbors those aspirations, then I think the U.S. is justified in dealing with that, if necessary, by military force," Cheney said.
Powell added, "When you can intercept a terrorist act that is heading your way or you can deal with a regime or a situation before it comes to a crisis level and threatens you, then it is an option that you should keep in mind and on the table."
Iraq's vice president denied Sunday that his country is trying to collect nuclear material or building up sites that U.N. weapons inspectors used to visit. Taha Yassin Ramadan, speaking to reporters in Baghdad, charged that the United States and Britain are seeking an excuse to attack Iraq.
"They are telling lies and lies to make others believe them," Ramadan said.
Bush administration officials expressed deep skepticism about giving Saddam another chance to open up his country to U.N. weapons inspectors. Officials say Bush is considering giving Saddam a last-ditch deadline for allowing unfettered access to weapons inspectors.
"The issue is not inspectors or inspections. That is a tool," Powell said. "Disarmament is the issue. And we will stay focused on that, and we believe that regime change is the surest way to make sure that it's disarmed."
Cheney said that if the United States led an attack on Iraq, American forces would have to stay there for a prolonged period afterward to ensure "we stood up a new government and helped the Iraqi people decide how they want to govern themselves until there was a peaceful stability."
War could be very costly, he said.
But, he added, "The danger of an attack against the U.S. by someone with the weapons that Saddam Hussein now possesses or is acquiring is far more costly than what it would cost us to go deal with this problem."
The Associated Press contributed to this report.