Firemen remove victims from a car shattered by a bomb blast on Embassy Row in Washington on Sept. 21, 1976. Orlando Letelier, former Chilean ambassador to the U.S., and Ronni Karpen Moffitt were killed in the blast. (AP)

Juan Gabriel Valdes, Chile’s new ambassador to the United States, is formally presenting his credentials to President Obama on Wednesday.

These formal events are not normally Loop-worthy happenings. But this one is different.

Turns out Valdes worked with another ambassador from Chile, Orlando Letelier,  who — older readers might recall — was assassinated in a 1976 car bombing on Sheridan Circle (that’s at Massachusetts Avenue near 23rd Street NW).

The bombing was organized by American expatriate Michael Townley, a wannabe-CIA agent  who worked for Chilean dictator Gen. Augusto Pinochet’s vicious secret police (DINA). Townley, who served about five years in prison for his role, implicated several anti-Castro Cubans in helping him carry out the hit.

Letelier, who was appointed ambassador here in 1971, was  imprisoned for a year after Pinochet’s 1973 coup. He  was released and went to the United States, where he continued to rally opposition to the dictatorship and to work to block foreign investment in Chile.

On the morning of Sept. 21, 1976, Letelier, his aide, Michael Moffitt, and Moffitt’s wife, Ronni, were headed down Massachusetts Avenue on the way to work at a liberal think tank, the Institute for Policy Studies,  when the bomb  went off as they rounded the circle — just across from the Chilean ambassador’s residence — killing Letelier and Ronni Moffitt. Michael Moffitt, in the back seat, survived.

“I was his other assistant,” Valdes told us. He had been a graduate student at Princeton but was asked to come down and help Letelier.

Letelier, who lived in Bethesda, “normally picked me up on Wisconsin Avenue and Massachusetts Avenue,” Valdes said, and Letelier asked him if he wanted a ride the next morning. “I told him I couldn’t because my wife wanted to go to the supermarket and I have to stay with my small children.”

“I was not in that car by a miracle,” he said.

Valdes said he loved being in Washington and was much honored to be ambassador. “But it brings back tragic memories as well.”