What is the Nuclear Non-Proliferation Treaty? Here's why it's still important
2019 Jul 19
Behrouz Kamalvandi, left, spokesman for Iran's atomic energy agency, listens to a man wearing a surgical mask, an official with the Ahmadi Roshan nuclear site in Natanz, Iran, during a news conference on May 20, 2019. IRIB News Agency via AP
Nearly 50 years old, the treaty has been signed by 190 countries – more than any other arms limitation treaty. But now Iran is threatening to withdraw.