Iran has endured three decades of US sanctions. Have they worked? Yes and no.
Iran has been under one form or another of US sanctions for more than 30 years. After the 1979 Islamic Revolution and the takeover of the US Embassy in Tehran, which saw 52 Americans held hostage in the country for 444 days, the United States seized extensive Iranian assets, the first iteration of financial restrictions that have only expanded in the decades since.
The eventual release of the hostages, on the day Ronald Reagan was sworn in as president, in some ways marked the high point of successful sanctions against Iran. Reagan's predecessor, Jimmy Carter, had promised to release about $8 billion of the seized money in exchange for the hostages' safe return.
In the decades since, one sanction after another has piled up, with a sharp impact on Iran's economy but little to show in the way of intended results. The US Department of the Treasury currently lists 34 executive orders and US laws that limit the financial activities of Iran and those who do business with the country. The latest round of US and international sanctions, passed this year, have gummed up the country's ability to sell crude oil, sending Iran's currency (the rial) to record lows and freezing its banks, including its central banks, from the routine transactions that make global commerce possible.