Less than a week after he unveiled the government's new color-coded threat assessment system, Homeland Security Director Tom Ridge -- who had only been on the job for five months -- said he had already weathered criticism and quips for the seemingly innocuous nature of a system addressing such a somber subject.

"I guess you know you've arrived when you become the subject of political cartoons," he told an Association of Firefighters conference last March 18. "There was one that was rather unique. As I was getting prepared to announce the level of threat, they had me dipping into a bag of M&M's to determine the color."

"I assure you," Ridge said. "while there is some art to the threat advisory system, there's a little bit more science than that."

The color-coded Homeland Security Advisory System rates the country's threat level in one of five stages: Low, signifying a low risk of terrorist attacks; Guarded, marking a general risk; Elevated, meaning a significant risk of a terrorist strike; High, signifying a high risk; and Severe, declared when the government determines a severe risk of a terrorist attack. According to Homeland Security Director Tom Ridge, U.S. officials developed the system to help law enforcement officials quantify the often-vague threat intelligence information they receive.

The White House recommends different responses for federal agencies for each of threat level, ranging from ensuring training in antiterrorism measures continues under the Low level to closing public facilities and constraining transportation systems during a Severe alert.

Changing the Threat Level
When the system was inaugurated in March 2002, the president put Attorney General John Ashcroft in charge of recommending changes to the national threat level on the five-tiered system in consultation with Ridge's homeland security office.

However, as the new Department of Homeland Security develops and organizes, administration of the advisory system will become the duty of the Under Secretary for Information Analysis and Infrastructure Protection, according to the White House's reorganization plan submitted in November. The department will administer the system and assume responsibility for issuing public alerts when necessary.

According to the president's directive establishing the advisory system issued last March, a change in threat level comes after officials review FBI, CIA and other intelligence data to determine whether the threat is credible, whether the information is corroborated, the degree to which the intelligence is specific or imminent and the severity of the potential consequences.

From there, the president's directive says, threat information can either be relayed throughout the country or to specific local assessment teams, since the system allows for different parts of the country to be placed on different stages of alert.

The national alert level has only been raised once from the Elevated or yellow stage. Ridge and Ashcroft increased the level to High, or orange, on Sept. 10, 2002 -- just ahead of the first anniversary of the terrorist attacks on New York and Washington.

According to Ashcroft, the threat level change came after conferring with the Homeland Security Council -- composed of Cabinet members and top White House advisers -- and with the president's approval.

Their recommendation to increase the threat level followed the discovery of specific information that al-Qaida operatives may have been planning an attack on U.S. interests to coincide with the Sept. 11 anniversary.

Ashcroft said that the threat level was not increased to its highest level, Severe, because intelligence pointed to an attack overseas. According to the attorney general, a move to the highest threat level "would have been triggered by specific credible intelligence and analysis pointing toward an imminent attack on the United States homeland."

After the Sept. 11 anniversary passed without an attack and the threat level was returned to Elevated on Sept. 24, Ridge wrote in a USA Today op-ed that the brief alert level hike proved the advisory system works.

"This is exactly what was envisioned when the system was launched in March," Ridge wrote. "We sought to communicate terrorist threats to the public in a clear and understandable way. And we coupled the threat levels with protective measures that can be tailored to the specific needs of a community, a business or even a family. It's a system made to be adapted, not just adopted."

He told a December 2002 gathering of employees soon to become part of the Homeland Security Department, for example, that private companies should plan their own safety precautions around the terror alert system.

He said that, while the advisory system specifies what government agencies should do at different alert levels, "we want companies to do the same thing... It's not just the level of threat; what do we do as a country based on our assessment of the threat to protect ourselves."

Praise & Criticism
The advisory system has not been without its critics, though. Some have argued the Bush administration has not fully defined the threshold for a change to the threat level.

"Ridge's warning lights are meant to reflect the terrorist threat, but instead they are cause for confusion and a staple joke on late-night television," writer John Miller said in a June 2002 edition of The National Review. "People don't need a set of lights with vague significance; they need useful information and practical advice."

After the FBI sent a warning to police in November about a possible "spectacular" al-Qaida attack planned against the U.S. and its interests – a warning that did not spark a threat level boost – The New York Times asked how Americans could be asked to prepare against a terrorist strike without more precise information.

"The only thing warnings this vague are good for is providing political cover in case of disaster," the Times wrote in a Nov. 17 editorial. "They offer no specific information about the location, timing or method of attack, and are all but useless tot he average citizen, or even to local law enforcement officers."

Others said it is more appropriate for such specific warnings to come from local or state governments rather than the federal advisory system.

"Nobody knows what the color levels mean. That's okay, they're declaring a level for the entire country. But the further down you drill, the more specific you need to become." Washington, D.C. Deputy Mayor for Public Safety Margret Nedelkoff Kellems told The Washington Post in November.

Despite the criticism, Ridge says state and local law enforcement officials are pleased with the system because it allows agencies to work off of the same page.

"[The advisory system] was embraced by the 50-plus homeland security advisers because we all think we need a standard vocabulary that says to the country what level of risk we're at," Ridge said in May. "I think the system is working very well."

-- Compiled by Greg Barber for the Online NewsHour