Richard Clarke , a former top adviser to three presidents, said the country simply can't protect its critical networks. Clarke joined a number of U.S. military and civilian experts at a conference to offer his dire assessment of America's cybersecurity.

Clarke, the author of "Cyber War: The Next Threat to National Security and What to Do About It," said if he were advising the President he would warn against attacking other countries because so many of them, such as China, North Korea, Iran and Russia, could retaliate with devastating cyber attacks that could destroy power grids, banking networks or transportation systems.

This story is part of Federal News Radio's daily Cybersecurity Update. For more cybersecurity news, click here.