Bush: Iraq Part Of Struggle Of Century

President Bush believes the war in Iraq is part of the ideological struggle of the 21st century, and says "the consequences for not achieving success are dire."

He made the comments in an exclusive interview Tuesday morning at the White House with CBS Evening News Anchor and Managing Editor Katie Couric. The interview will be broadcast tonight during a CBS News prime-time special, Five Years – How Safe Are We?, airs Tuesday at 10 p.m. ET/PT.

The special also features reports on homeland security and America's war on terror, including a report from Lara Logan, who traveled to Afghanistan; a report by Jim Stewart, who got an inside look at the FBI and who they are looking for; and Erin Moriarty, on how one major American city is using technology to keep an eye on you.

Following is an excerpt from Couric's interview with President Bush:

Katie Couric: "You have said we can't cut and run on more than one occasion. We have to stay until we win. Otherwise, we'll be fighting the terrorists here at home on our own streets. So what do you mean exactly by that, Mr. President?"

President Bush: "I mean that a defeat in Iraq will embolden the enemy and will provide the enemy more opportunity to train, plan, to attack us. That's what I mean. You know, one of the hardest parts of my job is to connect Iraq to the war on terror. I believe it. As I told you, Osama bin Laden believes it. But the American people have got to understand that a defeat in Iraq; in other words, if this government there fails, the terrorists will be emboldened, the radicals will topple moderate governments."

"I'm worried, Katie, strongly worried about a world if we lose our confidence and don't help defeat this ideology. I'm worried that 50 years from now, they'll look back and say how come Bush and everybody else didn't see the fact that this group of people would use oil to affect our economy? How come he didn't confront the Iranian threat and its nuclear ambitions? Why didn't you support the moderate governments there in the region? And I truly believe this is the ideological struggle of the 21st century. And the consequences for not achieving success are dire."

During the special, Couric also will examine security changes made since Sept. 11, 2001, and whether they have made Americans safer.

Portions of Couric's interview with the president also will be featured on CBS News.com and CBS Radio, including "Eye to Eye," Couric's daily, on-demand Webcast. The entire primetime special will available on CBSNews.com for on-demand viewing on Thursday, Sept. 7, at 2 a.m., ET.