The U.S. almost nuked itself - more than once.

In 1961 a plane carrying two hydrogen bombs broke apart over North Carolina. Each of those bombs held more power than the ones that destroyed Hiroshima and Nagasaki at the end of WWII. The violent impact caused the bombs' triggers to deploy. Out of 6 fail-safe interlocks, five went off in their proper sequence, only one switch "failed." The literal failure of two wires to cross prevented a devastating nuclear explosion like no civilian population has ever seen. One study by a U.S. nuclear weapon laboratory reports that over 1,200 nuclear weapons were involved in accidents from 1950 to 1968. The "accidents" include security breaches, lost weapons, failed safety mechanisms or accidents resulting from weapons being dropped or crushed in lifts, etc.