President Bush says attacks against U.S. troops in Iraq are meant to shake America's will and try to force an early pull-out of troops.

President Bush says foreign fighters are battling U.S. troops in Iraq because they realize that a democratic government in the heart of the Middle East would be a major blow to what Mr. Bush says is a hateful and dark ideology.

Mr. Bush spoke to a meeting of state legislators in Texas shortly after Marine commanders announced another 14 deaths Wednesday following the loss of seven Marines in western Iraq on Monday.

The president says it is a time of testing in Iraq and American troops are up to the challenge.

"The violence in recent days in Iraq is a grim reminder of the enemies we face," he said. "These terrorists and insurgents will use brutal tactics because they are trying to shake the will of the United States of America. That's what they are trying to do. They want us to retreat. They want us, in our compassion for the innocent, to say we are through. That's what they want."

President Bush says the terrorists will fail because they do not understand America's desire to protect itself. He says the more than 1,800 Americans who have lost their lives in Iraq died for a selfless cause.

"Their families can know that American citizens pray for them. And the families can know that we will honor their loved ones sacrifice by completing the mission, by laying the foundations for peace for generations to come," added President Bush.

American public opinion polls show falling support for the war in Iraq. President Bush has refused to set a timetable for the withdrawal of U.S. troops, saying that would allow the enemy to simply wait for them to leave.

Mr. Bush says U.S. troops will come home once Iraqi security forces are better able to fight the insurgency.

The president is at the start of a month-long vacation on his Texas ranch. White House officials say he will have six more speeches wrapping-up his accomplishments in Congress, including an energy bill, a highway bill, and the Central American Free Trade Agreement.

President Bush will have separate events during August with U.S. troops to talk about fighting terrorism and with older Americans to talk about reforming the pension program.

On Thursday, Mr. Bush welcomes Colombian President Alvaro Uribe to the ranch for private talks and questions from reporters.