The FBI has now ranked cyber crime as the third-greatest threat to U.S. national security, after nuclear war and weapons of mass destruction.
The Department of Defense said it has spent $100 million in the past six months responding to cyber attacks.
"We are finding ourselves in an ever-increasing, sophisticated environment where our networks at [the Department of Defense] are increasingly in a contested environment," Brig. Gen. John Davis of the U.S. Strategic Command told CNN. U.S. officials are concerned that other countries could use the Internet to infiltrate security networks or disrupt the power grid we rely on for electricity in homes and schools.
A recent report by the North American Electric Reliability Corp. revealed the electricity industry has not protected the nation’s electricity infrastructure from a cyber attack, particularly from trained operatives in Russia or China. "We know penetrations started more than 10 years ago. But we don't know all of them," James A. Lewis, a former federal computer security expert told the Washington Post.