GLYNCO, GA. - Firing back at conservative critics, President Bush defended his plan to overhaul immigration laws Tuesday and accused its opponents of "trying to rile up people's emotions" with misinformation.

In an exclusive interview with McClatchy Newspapers, Bush expressed his determination to fight for changes that would let millions of illegal immigrants gain legal status. He cast the debate as a struggle over America's soul and its reputation as a welcoming nation.

"I'm deeply concerned about America losing its soul. Immigration has been the lifeblood of a lot of our country's history," the president said during an interview on Air Force One. "I am worried that a backlash to newcomers would cause our country to lose its great capacity to assimilate newcomers."

Bush underscored his commitment to the proposed overhaul -- despite harsh criticism from some conservatives -- as he traveled to Georgia for a speech that blasted the legislation's critics.

"I'm sure you've heard some of the talk out there about people defining the bill. It's clear they hadn't read the bill. They're speculating about what the bill says, and they're trying to rile up people's emotions," he told an audience at the Federal Law Enforcement Training Center in Glynco, near Brunswick. "If you want to kill the bill, if you don't want to do what's right for America, you can pick one little aspect out of it, you can use it to frighten people. Or you can show leadership and solve this problem once and for all."

Bush acknowledged that the proposed overhaul faces a difficult time in Congress, where it's under attack from both ends of the political spectrum.

Conservative critics contend that it amounts to an amnesty program because illegal immigrants would be allowed to stay in the country after paying $1,000 fines. Some liberals complain that plans for a new temporary worker program are overly restrictive and would create a permanent underclass of foreign workers.

Some of the most vociferous criticism has come from conservative talk-show hosts who usually back the president. Commentator Rush Limbaugh has told his listeners that the legislation would doom the Republican Party and the nation.

The bill seeks to strike a balance between tougher border enforcement and a more welcoming policy toward the estimated 12 million immigrants who already are in the country illegally.

Bush hopes to push it through Congress with help from a bipartisan group of lawmakers that includes Sen. Edward Kennedy, D-Mass., a liberal stalwart, and Sen. Jon Kyl, R-Ariz., a staunch conservative. The president said he had no hesitations about working with Kennedy despite their sharp differences over Iraq and other issues.

"The reason why is he can get the job done," Bush said aboard Air Force One.