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. Last Updated: 07/27/2016

A Worried Washington Deploys Nuclear Sensors

WASHINGTON -- Alarmed by growing hints of al-Qaida's progress toward obtaining a nuclear or radiological weapon, U.S. President George W. Bush's administration has deployed hundreds of complex sensors since November to U.S. borders, overseas facilities and choke points around Washington. It has placed the Delta Force, the nation's elite commando unit, on a new standby alert to seize control of nuclear materials the sensors may detect.

Ordinary Geiger counters, worn on belt clips and resembling pagers, have been in use by the U.S. Customs Service for years. The newer devices are called gamma ray and neutron flux detectors. Until now they were carried only by mobile Nuclear Emergency Search Teams dispatched when extortionists claimed to have radioactive materials. Because terrorists would give no such warning, and because NEST scientists are unequipped for combat, the Delta Force has been assigned the mission of killing or disabling anyone with a suspected nuclear device and turning it over to the scientists to be disarmed.

The new radiation sensors are placed in layers around some fixed points and temporarily at designated "national security special events" such as last month's Olympic Games in Utah. Allied countries, including Saudi Arabia, have also rushed new detectors to their borders after American intelligence warnings. To address the technological limits of even the best current sensors, the Bush administration has ordered a crash program to build next-generation devices at the three nuclear national laboratories.

These steps join several other signs the Bush administration's nuclear anxieties have intensified since American-backed forces routed Osama bin Laden's al-Qaida network and its Taliban backers in Afghanistan.

A high-ranking official said, "the more you gather information, the more our concerns increased about al-Qaida's focus on weapons of mass destruction of all kinds."

In "tabletop exercises" conducted as high as the Cabinet level, Bush's national security team has highlighted difficult choices the chief executive would face if the new sensors pick up a radiation signature on a boat steaming up the Potomac River or a truck heading for the capital. Participants in those exercises said the gaps in their knowledge are considerable.

The current consensus government view is that al-Qaida probably has acquired the lower-level radionuclides Strontium-90 and Cesium-137, many thefts of which have been documented in recent years. These materials cannot produce a nuclear detonation but are radioactive contaminants. Conventional explosives could scatter them in what is known as a radiological dispersion device, known colloquially as a "dirty bomb." The number of deaths that may result is hard to predict. but probably would be modest.