Operation Eagle Claw.
Responding to the international crisis created in 1979 when the Khomeini revolution in Iran took over the US embassy in Tehran and took scores of Americans hostage, President Carter ordered US Special Operations Forces into action. Unfortunately, disaster struck Operation Eagle Claw at a location in Iran codenamed Desert One. There an accident killed eight American troops and wounded several others. The mission came to a premature end.
The community web site Kuro5hin hosts a series of informative articles on the ill-fated mission. In light of recent events in Iran, it is useful to look back on the recent history.