NICOLE GRAJEWSKI is a Fellow in the Nuclear Policy Program at the Carnegie Endowment for International Peace and an Associate with the Project on Managing the Atom at the Harvard Kennedy School. She is the author of Russia and Iran: Partners in Defiance From Syria to Ukraine.

TEHRAN -- Iran will make an immediate, decisive reaction to any attack on its nuclear facilities, Iranian Foreign Minister Seyed Abbas Araghchi has warned.

Its nuclear programme is a rare area where Iran might claim to retain the initiative. Late last year Iran was producing around 7kg of uranium enriched to 60%—a stone’s throw from weapon’s grade—each month,

Shortly before Donald Trump’s inauguration, however, the flag was quietly removed. There was no official explanation from Iranian officials. But the move captured a quiet shift in Tehran’s thinking, in what is shaping up to be its most consequential year since the 1980s Iran-Iraq war: with the country at its most vulnerable point in years,