Almost two years after Hurricane Katrina devastated the U.S. Gulf Coast, the National Guard says it remains ill-prepared to respond to a sudden disaster. Some lawmakers are calling for better planning in the event of a large-scale natural disaster or terrorist attack. Leta Hong Fincher has more.

Army Lieutenant General Steven Blum

But Blum says the National Guard is still unprepared for a sudden, major disaster: not just a hurricane, but a terrorist nuclear attack.

"In a predictable event,” explained the general, “we can make do with not having enough equipment, because we can move it around. In a no-notice event, we're at risk, and we're at significant risk."

Disasters such as floods, hurricanes and nuclear attacks are responded to by the National Guard

"Policymakers whom they [defense scholars] questioned in Washington, they found, continue to believe that state and local officials will be able to control the situation the day after a nuclear attack,” said Mr. Lieberman. “Yet [Ashton] Carter and [William] Perry argue that as the fiasco after Hurricane Katrina suggests, most cities and states will quickly be overwhelmed by the magnitude of the humanitarian, law-and-order and logistical challenges of responding to a nuclear detonation."

Lieberman and Republican Senator Susan Collins have called on the U.S. Government Accountability Office to investigate current national disaster-response plans, to make sure they are complete and well-understood.