Tons of chemical weapons in the U.S. stockpile, mostly consisting of mustard gas and various nerve agents.

Tons of chemical weapons that Syria is believed to have.

The year the U.S. military believes it will finally be done getting rid of its chemical weapons, which are stored in facilities near Colorado Springs, Colo., and Richmond, Ky. The original deadline was 2007.

Tons of chemical weapons the United States built up from World War I until 1968. Pressure in the 1970s caused the country to cease production of chemical weapons and eventually start destroying them.

Tons of chemical weapons amassed by Russia in that same time period.

$40 billion
Estimated total cost to the U.S. government of destroying all of its chemical weapons — if the task is finished on schedule.

Percentage of the U.S. chemical weapons supply that has already been destroyed.

$500 million
Amount spent by the United States each year to assist other countries in destroying their stores of chemical, biological, and nuclear weapons.

Estimated number of nuclear warheads possessed by the United States.

Operational U.S. nuclear warheads assigned to land-based missiles, nuclear submarines, and bombs ready for deployment in military aircraft.

Operational nuclear warheads in Russia.

Maximum estimate of warheads that Kim Jong Un can build with North Korea's existing supply of plutonium.

Nuclear weapons possessed by the United States in 1967.

9 megatons
Amount of energy released by the B53 nuclear bomb, which is 900 times more powerful than the bomb dropped on Hiroshima. The bomb was dismantled in Amarillo, Texas, in 2011.

Nuclear weapons (not counting warheads in storage or awaiting dismantlement) allowed by the New START Treaty, signed by Russia and the United States in 2010.

Sources: Associated Press, BBC, CNN, Brookings Institute, The Guardian (2), The Washington Post (2)