Manhattan ? President Bush on Monday rejected critics’ assertion that he broke the law by authorizing domestic eavesdropping without a warrant, saying he was doing what Congress authorized him to do to protect Americans from terrorist attacks.

With congressional hearings set to begin on this issue Feb. 6, Bush kicked his administration’s new intensive public relations effort to win support for the program run by the National Security Agency. As part of that, he gave it a new label – the Terrorist Surveillance Program.

Bush noted that hearings will open in Congress soon, and Sen. Pat Roberts, R-Kan., who accompanied the president here, was among the lawmakers on Capitol Hill who were given regular updates about the surveillance by the White House. Sen. Arlen Specter, R-Pa., chairman of the Judiciary Committee, will preside over the hearings.

“It’s amazing that people say to me, ‘Well, he’s just breaking the law,” the president said, with Roberts sitting behind him on stage at Kansas State University. “If I wanted to break the law, why was I briefing Congress?”

Bush said the spying program was targeted at communications between people in the United States and al Qaida associates overseas. He said he made sure he was acting within the law before authorizing the program after his aides suggested it.

“I’m mindful of your civil liberties and so I had all kinds of lawyers review the process,” Bush told some 9,000 students, soldiers and dignitaries in the audience.

Critics have said the president broke the law by authorizing the eavesdropping without a judge’s approval and by failing to fully consult with Congress. The White House told congressional leadership about the program, but not all members of the intelligence committees.

Bush said a congressional resolution passed after Sept. 11, 2001, that authorized him to use force in the fight against terrorism, also allowed him to order the top-secret program. That operation was disclosed last month by The New York Times.

“Congress gave me the authority to use necessary force to protect the American people, but it didn’t prescribe the tactics,” Bush said, adding that the government needs to know why people linked to al Qaida are calling into the U.S. “One of the ways to protect the American people is to understand the intentions of the enemy.”

A majority of Americans – 56 percent – said the Bush administration should be required to get a warrant before monitoring electronic communications between American citizens and suspected terrorists, according to an AP-Ipsos poll earlier this month.

When people have been asked in other polls to balance their worries about terrorist threats against their worries about intrusions on privacy, fighting terror is the higher priority.

Bush’s appearance was the fourth in the last six weeks in which he’s taken questions from the audience. But Kansas State offered the largest audience yet, with a coliseum full of roughly 9,000 people who got tickets distributed by the university. Six thousand were students, 800 were soldiers from nearby Fort Riley who just returned from Iraq, officials said.

The White House says none of the questions was prescreened. The site chosen for Monday’s event, however, was in friendly Bush territory in the reliably “red” state of Kansas.

Bush received a hero’s welcome, with long standing ovations and loud applause as he defended his most controversial positions. There was a noisy crowd of a couple hundred sign-waving anti-war protesters outside the arena where Bush appeared. “Wage war, not peace!” they chanted to a drumbeat.

While the president was in Kansas, anti-abortion activists were gathering in Washington and elsewhere to protest the 33rd anniversary of the Supreme Court decision legalizing abortion. As he has in past years, Bush called in his support rather than attend in person.