** FILE ** U.S. Air Force Gen. Gene Renuart, gestures during a news conference at Central Command Center, Doha, Qatar in this April 10, 2003 file photo. Renuart, the military commander in charge of defending the U.S. homeland, said he believes there are al-Qaida cells in the U.S. or people working to create them. (AP Photo/Richard Lewis, File)
WASHINGTON (AP) -- Al-Qaida terrorists may be plotting more urgently to attack the United States to maintain their credibility and ability to recruit followers, the U.S. military commander in charge of domestic defense said.
Air Force Gen. Gene Renuart, chief of the U.S. Northern Command, also told reporters Thursday he has not seen any direct threats tied to the U.S. presidential elections. But he said it would be rash to think that such threats are not there.
"We need only to look at Spain and see that they're certainly willing to try to do something that is significant that could affect an election process," Renuart said. "I think it would be imprudent of us to let down our guard believing that if there's no credible threat that you know of today, there won't be something tomorrow."
While he said that U.S. authorities have thwarted attacks on a number of occasions, he said terrorist cells may be working harder than ever to plot high-impact events. He did not point to any specific intelligence that authorities have received but said the "chatter" they are hearing "gives me no reason to believe they're going to slow down" in their efforts to target the U.S.
"If an organization like that is to maintain credibility and continue to grow more of its extremists, it has to show tangible results," Renuart said. "So I think there may be a certain sense of urgency among that organization to have an effect. So it would tell me that they're trying harder."
Asked about the terror threat, Homeland Security spokesman Russ Knocke said, "There continues to be no credible information telling us about an imminent threat to homeland at this time."
In July, U.S. intelligence analysts, in a threat assessment, concluded that al-Qaida had rebuilt its operating capability to a level not seen since just before the Sept. 11, 2001, terrorist attacks. The report said the terror network had regrouped along the Afghan-Pakistan border, but it also noted that officials knew of no specific credible threat of an attack on U.S. soil.
About the same time, Homeland Security Secretary Michael Chertoff raised eyebrows when he said he had a "gut feeling" that the United States faced a heightened risk of attack.
On Thursday, however, Chertoff said the U.S. has successfully lowered the risk of a large-scale domestic terrorist attack for the near future.
"We have significantly reduced the risk of a major attack in the short term," Chertoff told a group of editors at The Washington Post in a report posted online Thursday.
Chertoff said the U.S. effort was one of the reasons there has been an increase in attacks by Islamic extremists in Europe. Improvements in U.S. traveler screening and border security have shifted the focus of al-Qaida operatives and sympathizers to Europe, he said.
Renuart said that of the more than a dozen daily events that Northern Command responds to - ranging from natural disasters to threats - two or three may have the potential to be terrorist incidents.
The chatter, which included public audio and video tapes released on the Internet by al-Qaida leaders, suggests that they are looking for a way to have a big impact again, he said. Pressed for details, he said the chatter was more common but "whether that's louder or more ominous, I'm not sure I'm ready to draw that conclusion."
He did, however, repeat his assertion - which he first made in July - that he believes there are al-Qaida cells or sympathizers within the United States.
President Bush, in a speech Thursday, also said the United States remained under threat from terrorists. Marking the fifth anniversary of the creation of the Homeland Security Department, Bush said that in the aftermath of the Sept. 11 attacks "it was hard to imagine that we would reach this milestone without another attack on our homeland."
Yet he said, "On this anniversary, we must also remember that the danger to our country has not passed. Since the attacks of 9/11, the terrorists have tried to strike our homeland again and again. We've disrupted numerous planned attacks - including a plot to fly an airplane into the tallest building on the West Coast and another to blow up passenger jets headed for America across the Atlantic Ocean."
Bush said the lesson is clear: "The enemy remains active, deadly in its intent - and in the face of this danger, the United States must never let down its guard."
AP White House Correspondent Terence Hunt and AP writer Eileen Sullivan contributed to this report.
© 2008 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.