Nuclear security

The Pentagon recently admitted there are "systemic problems across the nuclear enterprise." Thanks to arms-control treaties and the end of the Cold War, the U.S. has reduced its stockpile of nuclear weapons from 31,000 to about 4,800 over the last 48 years.

But as fears of nuclear war eased, the government failed to adequately maintain and update this immensely dangerous arsenal, which still contains enough collective destructive force to lay waste to every country on Earth.

The U.S.`s 450 intercontinental ballistic missiles (ICBMs) are stored in decaying 60-year-old nuclear silos in Montana, North Dakota, and Wyoming that look like a poorly maintained Cold War museum.

The demoralized Air Force personnel safeguarding the weapons have been plagued by scandals reaching to the very top of the command structure - including drug rings, mislaid missiles, and widespread cheating on readiness tests. Today, the real nuclear threat to America isn`t an enemy strike, says Air Force Lt. Gen. James Kowalski. It`s "an accident. The greatest risk:is doing something stupid."

The dangers of our aging nuclear arsenal