The death of North Korean leader Kim Jong-il has riveted international attention on the threat of nuclear weapons. Kim was widely reported to have been pursuing nuclear warheads and ballistic missiles to deliver them, and he presided over a pair of nuclear bomb blast tests (confirmed by seismograph). No one outside North Korea knows whether the secretive, totalitarian nation possesses an actual warhead. And no one is quite sure where Kim's youngest son and presumed successor Kim Jong-un stands on the goal of assembling a competitive nuclear arsenal.

It could only take one nuclear device and one maniacal leader to wreak global havoc, but the U.S. and seven other nations worldwide have many nuclear warheads in their arsenals. The latest tally (pdf), made at the end of 2009 by Robert S. Norris and Hans M. Kristensen at the Natural Resources Defense Council in Washington, D.C., is below. Stockpiles in Russia and the U.S. dwarf those of other countries.

  • Russia—13,000 nuclear warheads
  • U.S.—9,400
  • France—300
  • China—240
  • U.K.—180
  • Israel—80 to 100
  • Pakistan—70 to 90
  • India—60 to 80
  • North Korea—unknown

Norris and Kristensen estimate that 4,850 of Russia's warheads are operational; the rest are retired or waiting to be dismantled under arms reduction treaties. About 5,200 of the U.S. warheads are considered operational. In their report, Norris and Kristensen noted that "we are not aware of credible information on how North Korea has weaponized its nuclear weapons capability." They add that U.S. Air Force intelligence did not indicate that any of the country's ballistic missiles were capable of carrying a nuclear warhead at that time.