Terror probe: Why is threat level still yellow?

DHS didn't change the threat level before and after agents nabbed Najibullah Zazi because advisories to local police were deemed sufficient.

The investigation into a potential Al Qaeda plot in the US has triggered a raft of warnings from federal authorities about suspicious activity around stadiums, hotels, and train stations, among other places. But it hasn't moved the color-coded terror alert system.

The Department of Homeland Security's national threat level was yellow – or elevated – before and after counterterrorism agents nabbed Najibullah Zazi. He's the Denver airport shuttle driver at the center the investigation into an alleged plot that authorities say involves plans to build peroxide-based bombs.

In fact, the alert system has been static since 2006, when British officials foiled a plan to blow up transatlantic flights headed to North America from London. That caused the warning to jump to red (severe) for those flights and to orange (high) for general attacks.

But there's no reason this latest terror investigation should have raised the terror alert, says James Carafano, a homeland-security expert at the Heritage Foundation in Washington.

"What is widely perceived as a system to update the American people about terrorist threats is not really designed for that," he says. "When you raise the color-coded system, it's a blunt instrument" that triggers specific actions by law enforcement and federal agencies.

For instance, if the system moves from yellow to orange, DHS recommends that federal agencies restrict various facilities and possibly cancel events. With this latest plot, says Mr. Carafano, not enough was known to merit that sort of precaution. Instead, he says, the advisories that federal agents sent local police were enough to ensure extra vigilance among law enforcement and the public.

The Homeland Security Advisory System was built after 9/11, and now, Carafano says, the "national readiness system" needs to be reevaluated. "This whole incident demonstrates how little utility it has as a terrorist alert system," he says.

The Obama administration commissioned a task force to examine the color-coded alerts and recommend changes to a system that has been mocked on late-night television. Some critics have charged that during the Bush administration, it was too closely aligned with political purposes.

"The Task Force members agreed that, at its best, there is currently indifference to the Homeland Security Advisory System and, at worst, there is a disturbing lack of public confidence in the system," the group of security experts and public officials concluded in its report, which was completed this month.

While the group was split over whether to scrap the color-coded system, they recommended creating a new base line: blue, meaning guarded, which is currently one step above the lowest level (green). This would replace the practice now of keeping the threat level on yellow. Another recommendation: When the alert level is raised because of a possible terrorist threat, it should be lowered within 15 days "unless credible intelligence shows a reason to keep it elevated."

The task force said, "The escalators need to run both ways."

Now that the task force's work has been completed, Homeland Security Secretary Janet Napolitano is expected to make recommendations to the White House.

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The current terror case

Evidence is still emerging in the case involving an Denver airport shuttle driver, but experts and officials say the details suggest the plan is similar to attacks in London and Madrid. Click here to read more.

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