Weapon of mass destruction
The only country to have used a nuclear weapon in war is the United States, which dropped two atomic bombs on the Japanese cities of Hiroshima and Nagasaki during World War II. There are eight countries that have declared they possess nuclear weapons and are known to have tested a nuclear weapon, only five of which are members of the NPT. The eight are China, France, India, North Korea, Pakistan, Russia, the United Kingdom, and the United States.
Views on the nuclear program of Iran
Iranian politicians compare its treatment as a signatory to the NPT with three nuclear-armed nations that have not signed the NPT: Israel, India, and Pakistan. India and Pakistan developed an indigenous nuclear weapons capability, and it is widely suspected that Israel has as well: Israel by 1966, India by 1974, and Pakistan by 1990.