On Saturday, President Trump invoked history when tweeting out a threat to destroy “52 Iranian sites … some at a very high level & important to Iran & the Iranian culture.” He said the potential targets represent the 52 Americans who were held hostage there for 444 days from 1979 to 1981.

On Monday, Iranian President Hassan Rouhani invoked history right back in response to Trump’s threat.

His hashtag “#IR655” refers to Iran Air Flight 655, a commercial jet shot down by the U.S. military by mistake on July 3, 1988, killing all 290 civilians and crew on board, including 66 children.

Although the incident is nearly forgotten in the United States, it is etched deeply in memory in Iran, where the country is mourning the U.S. airstrike that killed Iranian military commander Qasem Soleimani.

In 1988, the long war between Iraq and Iran was close to ending. At the time, the United States supported Iraq and its leader Saddam Hussein in their fight against Iran. U.S. Navy ships patrolled the Persian Gulf to protect shipping routes.

On the morning of July 3, the cruiser USS Vincennes was engaged in a skirmish with Iranian gunboats in the Strait of Hormuz. Not far away, in the coastal city of Bandar Abbas, an Iran Air commercial jet took off for a routine flight to Dubai. This flight was frequently packed with weekend shoppers going to Dubai for jewelry and electronics, The Washington Post’s Valerie Strauss reported.