<em>The Iran-Contra scandal or the Iran-Contra affair.</em>
Explanation:
During this time, Ronald Reagan was president. He ended up being under a lot of fire since a lot of people suspected him of knowing something about this or even being hands-on about it.
This scandal had to do with the United States government or even some high up officials giving Iran weapons. Iran was in a war with Iraq during this time, so it would obviously help Iran to get weapons.
In exchange for weapons, the United States government would get hostages, this has to do with the hostage crisis centered in Iran.
After all of this, Ronald Reagan apologized and took complete blame for what happened.