U.S. Set to Test Missile Defenses Aboard Airlines

The tests are being financed by the Department of Homeland Security, which has been directed by Congress to move rapidly to take technology designed for military aircraft and adapt it so it can protect the nation's 6,800 commercial jets. It has so far invested $120 million in the testing effort, which is expected to last through next year.
Yet even before the tests begin, some members of Congress, and several prominent aviation and terrorism experts, are questioning whether the rush to deploy this expensive new antiterrorism system makes sense.
Homeland Security officials have repeatedly cautioned that no credible evidence exists of a planned missile attack in the United States. But there is near unanimity among national security experts and lawmakers that because of the relatively low price and small size of the missiles, as well as the large number available on the black market, they represent a legitimate domestic threat.