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SIOUX CITY, IOWA: Ron Paul told Iowa voters on Friday that he would not launch a preemptive strike on Iran because "they don't threaten our national security."

"If some other country thought they had to go to war with them, that is their business," he said, adding there is no proof Iran is building a nuclear weapon.

A recent IAEA report said that Iran's pursuit of nuclear technology over several years could be consistent with the building of a bomb. And Secretary of Defense Leon Panetta gave Iran "about a year, perhaps a little less" before it could have a nuclear weapon.

Paul's position on Iran is one that has drawn criticism from his GOP rivals.

On Friday, Paul was responding to a question from an Iowa voter who asked the Texas Congressman whether he could conceive of a situation where he would preemptively declare war on a country.

Paul admitted that the president does need the consent of Congress to declare war, but did say, "If battleships are off our shore, an imminent attack, the president has an obligation to respond."

But in the case of Iran, Paul provoked his rivals and exclaimed, "they can't even produce enough gasoline for their automobiles."

With his bump in the polls, Paul's GOP opponents, who see national defense as his weakness, have hit hard this week.

"Ron Paul thinks it would be fine if the Iranians obtained nuclear weapons," Michele Bachmann said.

"You don't have to vote for a candidate who will allow Iran to have a nuclear weapon to wipe Israel off the face of the earth," echoed Rick Perry.

"One of the people running for president thinks it's O.K. for Iran to have a nuclear weapon. I don't," said Mitt Romney.

Paul admitted on Friday that the criticism "baffles me a whole lot," adding what is dangerous is endless wars and expanding government.

The Texas congressman rarely attacks his rivals at campaign stops, instead using campaign ads and interviews.

He told Bloomberg News on Friday that he might not be able to support any of his rivals because they embraced the status quo in Washington, admitting that his rivals don't want to cut anything, audit the fed or bring significant change in government, and "that's a problem for me," Paul said.

Ron Paul placed second in support among Iowa voters in the latest NBC News-Marist University polls; he came in at 21%, with Romney at 23%.

Paul has drawn several hundred people at all three campaign stops today and has 500 college students canvassing for him in Iowa and New Hampshire.

Paul will be back on the campaign trail on Monday, stumping with son Rand as they make five campaign stops across Iowa.

In the meantime, the Texas congressman will be spending the weekend with his wife in Texas.

When asked by a reporter if that's an indication that he's feeling confident, a visibly smiling Paul looked up and replied, "I never talk in those terms."