Cops on the beat, airport security personnel and officials who issue U.S. travel visas would have access to a single anti-terrorist "watch list" containing more than 100,000 names under orders issued Tuesday by President Bush.

The Terrorist Screening Center (search), a 24-hour, 7-days-a-week operation under the FBI's lead, will merge a patchwork of a dozen existing lists currently maintained by nine different federal agencies — but not always accessible to the officials who need them.

The CIA (search) will provide information on individuals with ties to international terror organizations, such as Al Qaeda (searchand Hezbollah (search). The FBI (search) will feed the center its data on individuals sought for domestic terror activities, such as bombing abortion clinics or torching sport-utility vehicles.

Homeland Security Secretary Tom Ridge said the center would "get this information out to our agents on the borders and all those who can put it to use on the front lines, and get it there fast."

Critics in Congress and elsewhere have repeatedly chided the government for its failure to share information about terrorists prior to the attacks on Sept. 11, 2001. The recent investigation by the House and Senate intelligence committees concluded this failure cost the FBI a chance to detect two of the 19 hijackers.

Larry Mefford, the FBI's top counterterrorism official, told reporters that had the new system been in place in 2001, those two hijackers — Khalid al-Mihdhar and Nawaf al-Hazmi — might have been apprehended before they boarded the plane they helped crash into the Pentagon.

The CIA had discovered their connections to Al Qaeda in 2000, but their names weren't put on any watch list until August 2001 and were never shared with the FBI, which had an informant in San Diego who knew both.

California Rep. Jane Harman, top Democrat on the House Intelligence Committee, praised the move by the Bush administration but said it was long overdue.

"Had this action been in place prior to 9-11, we may have been able to disrupt the plot be denying entry to or detaining would-be terrorists," Harman said.

Among the existing databases to be consolidated are the Transportation Security Administration's "no-fly" list of terror suspects barred from air travel; the State Department's massive TIPOFF list, which is checked when visas are issued; and the FBI's National Crime Information Center list of convicted felons, fugitives and other wanted people used by police nationwide.

FBI and Homeland Security Department officials portrayed the system, expected to be up and running Dec. 1, as a near-instantaneous way for all the government's anti-terror information to be accessed by police, security personnel and U.S. embassy officials.

"We're not talking about creating new lists," said Larry Mefford, the FBI's top counterterrorism official. "The purpose is to improve our capabilities and not to create new lists."

Still, there are a number of bugs to be worked out. One of the most challenging is to guard against duplicate or incorrect names from causing trouble for innocent people. Another is to devise a way for people to appeal if they believe they are wrongly included on the database.

Anthony Romero, executive director of the American Civil Liberties Union, said the government must take care not to create a permanent "blacklist" from which it is impossible to escape.

"Our greatest concern is that innocent people might be wrongly labeled as terrorists, with little or no recourse to clear their names," Romero said.

In addition, it's not clear what a local police officer might do if a person on a terrorist database is stopped for a traffic violation but there is no legal authority, such as an arrest warrant, for the person to be detained.

Mefford said authorities have unspecified "contingencies" for such instances if they involve an especially dangerous suspected terrorist, but conceded that in some cases the local officer might be advised to let the person go.

"At least we'll know where they were," Mefford said. "We'll have some leads to follow up on."

The new center, in the works for months, was officially created by a directive issued Tuesday by the president. Employees from the CIA, FBI and departments of Justice, Homeland Security and State will staff the center, to be located in northern Virginia.