In Smithsonian Magazine, Michael Dobbs writes about the "football," the briefcase which allows the Commander-In-Chief to issue orders for a nuclear strike. It dates back to JFK's administration and, thankfully, its capabilities haven't been put into action -- yet.
With the threat of nuclear attack from another nation much less likely than another 9/11-style attack, the usefulness of the football is in doubt. It is supposed to be carried by a military aide who is with the President at all times, but the system is about as perfect as the Secret Service's protection plan for the White House...
For the Football to function as designed, the military aide must be nearby the commander in chief at all times and the president must be in possession of his authentication codes. Both elements of the system have failed on occasion. According to the former chairman of the Joint Chiefs of Staff, Gen. Hugh Shelton, Clinton mislaid his laminated code card, nicknamed the “Biscuit,” for several months in 2000. “This is a big deal, a gargantuan deal,” the general complained in his 2010 autobiography, Without Hesitation: The Odyssey of an American Warrior.Read Dobbs' full story here.
An even closer brush with disaster came during the attempted assassination of Reagan in March 1981. During the chaos that followed the shooting, the military aide was separated from the president, and did not accompany him to the George Washington University hospital. In the moments before Reagan was wheeled into the operating theater, he was stripped of his clothes and other possessions. The Biscuit was later found abandoned, unceremoniously dumped in a hospital plastic bag.