The Wall Street Journal | Asa Fitch and Josh Ulick: U.S. sanctions on Iran date to 1979, when the Carter administration froze Iranian assets in response to the Iran hostage crisis, in which 52 Americans were held for more than a year at the U.S. Embassy in Tehran.

Sanctions pressure rose in the late 1990s and early 2000s under the Clinton and Bush administrations, responding to Iran’s advancing nuclear program and its support for Hezbollah and its support for Palestinian militant groups fighting Israel.

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