During his appearance Thursday on behalf of Alabama Gov. Bob Riley, the president called a U.S. withdrawal from Iraq the greatest danger facing the United States because a withdrawal would encourage terrorists and help them find new recruits, The Washington Post (NYSE:WPO) reported.

Leaving Iraq also would expose the United States to lethal and economic threats, the president said.

Bush's also provided comments to the National Intelligence Estimate, which the president reluctantly released a part of after other portions were leaked, the Post said. The report by the nation's 16 intelligence agencies claimed seeking out terrorists and preventing attacks have become more difficult because the terrorism threat has become more dispersed.

Bush said Democrats critical of his policy in Iraq offer "endless second-guessing," while Republicans "know the enemy wants to attack us again," the Post said.

Senate Minority leader Harry Reid, D-Nev., said in the Post that Bush has no credibility regarding national security. "(T)he American people can see the damage his tough talk has done to America's safety," he said in the Post report.