The Obama administration is considering abandoning the color-coded terrorism-alert system that became a barometer of the nation's anxieties after the Sept. 11, 2001, attacks and replacing it with advisories that provide more detailed guidance on emerging threats.
A proposal drafted by the Department of Homeland Security and submitted to the White House urges a shift toward more-tailored threat warnings and the dismantling of the five-color scheme that was often mocked for alarming people but providing little useful guidance on how they should respond, U.S. officials said.
"The goal is to replace a system that communicates nothing with a system that communicates precise, actionable information based on the latest intelligence to law enforcement, the private sector and the American public," said a senior Homeland Security official, speaking on the condition of anonymity because deliberations are continuing.
The existing system, in place since 2002, uses a band of colors - green, blue, yellow, orange and red - in a stoplight-like arrangement to convey the nation's terror-alert status. Green indicates a low threat level and red a severe risk of attack.
The alerts were once routinely displayed in airports and, at times, on television newscasts to underscore the level of concern about the prospect of a terrorist attack. But in a measure of how much the system has faded in importance, officials said that the last time the color changed was in 2006.
Dozens of terror plots have surfaced since then, including a failed attempt to blow up a Detroit-bound airliner on Christmas Day last year and the botched bombing of Times Square by a Pakistani-born U.S. citizen in May.
Experts said the color system had become an almost forgotten relic of the nation's frantic post-Sept. 11 response.
"Over time, its utility eroded, and people just didn't notice anymore," said Bruce Hoffman, a terror expert at Georgetown University. "Something more formal and more specific will probably be taken more seriously."
Homeland Security officials declined to provide details on the system the department has proposed, saying that the recommendations are being reviewed by other agencies, including the Justice Department and the White House. But officials pointed to the warnings issued last month about possible terror strikes overseas as an example of how the government wants the new system to function.
On Oct. 3, the State Department issued a travel alert warning U.S. citizens of possible terror attacks in Europe. The alert did not instruct people to cancel their travel plans but told of fresh intelligence about al-Qaeda plots that might be aimed at public transportation systems and other targets.
The threat in Europe has yet to subside. This month, German Interior Minister Thomas de Maizier said there were "serious indications" that attack plans were underway.
U.S. officials said the new system would assume a baseline state of heightened public awareness and would be built around two broad threat categories: elevated and imminent. The latter would be instituted for no more than a week at a time, officials said, and would be accompanied, when possible, by specific information on the nature of the threat.
"It could come in the form of a DHS-FBI bulletin to local law enforcement, a briefing to cargo carriers" or a statement from public officials "to residents of a particular metropolitan area," a Homeland Security official said.
The recommendations grew out of a review requested last year by Homeland Security Secretary Janet Napolitano. If the color-coded system is scrapped, it would mean the demise of one of the signature counterterrorism measures of President George W. Bush.
The proposed changes come at a time when holiday travelers are facing stringent new screening procedures at airports across the country, including full-body scans and pat-downs that have prompted protests from some travelers.
Those measures were triggered by the airline plot that was thwarted Dec. 25 when passengers subdued a Nigerian man accused of attempting to ignite an explosive device hidden in his underwear.
More recently, the government has scrambled to update cargo-screening procedures after authorities in England and Dubai intercepted parcels packed with explosives that had been shipped from Yemen to addresses in Chicago.
Homeland Security officials said the department routinely sends threat information to local authorities as well as private-sector groups, even when the public threat level doesn't change.
The department has worked with the hotel industry to bolster security after a 2008 massacre of guests at the Taj Mahal Palace & Tower hotel in Mumbai. The effort includes "training their workforce on what to look for, what the signs are," a Homeland Security official said.
The color-coded threat level has been adjusted 16 times since the system's inception on March 12, 2002. It reached red only once, on Aug. 10, 2006, amid a disrupted al-Qaeda plot targeting transatlantic flights.
Since then, the threat level has been static: orange (high) for the aviation sector and yellow (elevated) for the rest of the country.