On a recent afternoon in a popular cafe in Washington’s Adams Morgan neighborhood, Murat Yasa, a veteran Kurdish activist, tears up, his burly frame shaking as he recalls the orgy of violence that erupted outside the residence of the Turkish ambassador to Washington on May 16, 2017. Yasa, a 61-year-old US citizen, was among a group of Kurdish men and women who had gathered in Sheridan Circle to demonstrate against President Recep Tayyip Erdogan. The Turkish leader was in town to meet with President Donald Trump that day and the group was peacefully protesting Turkey’s repression of their brethren with a volley of salty accusations. “Baby killer,” Yasa shouted as Erdogan’s sedan pulled into the driveway.

It wasn’t long before Yasa found himself semi-conscious in hospital along with nine other protesters after Erdogan’s bodyguards and thugs for hire set upon them. One yelled “Die Kurd” as they kicked and struck the demonstrators with discernible glee. Lucy Usoyan, a young Yazidi woman who was repeatedly hit on the head, fell unconscious, despite Yasa’s best efforts to shield her. The images captured on video and later subjected to forensic scrutiny leave no doubt as to what had transpired. “I didn’t know if I would ever see my children again,” Yasa said. “I thought I was dying.”

Nineteen months on, Yasa, who runs a floor-laying business in Virginia, suffers from dizzy spells and memory loss. His hands are unsteady. He is, he said, an altered man. But Yasa’s desire for justice is unwavering, with potentially bruising effects on Turkey’s already turbulent relationship with the United States.

In May, Yasa and a dozen and a half fellow victims filed a civil action lawsuit in US federal court against Turkey. They are demanding at least $300 million in compensation on multiple counts ranging from bodily harm to psychological trauma — including, in at least one case, damage to conjugal relations.