The brutal and crackdown on protesters killing tens of thousands has been a “sledgehammer” to Iranians everywhere, said Dr. Meir Javedanfar, an Israeli-Iranian expert on the government led by Ayatollah Ali Khameini.

“The people of Iran have just gone through their own Babi Yar massacre,” Javedanfar said on the Haaretz Podcast, referring to the largest single mass-killing during the Holocaust. “The Nazis killed 30,000 people in the space of two days. The Iranian regime – if we accept the 30,000 number – has done the same in less than a month. … The level of cruelty is unlike anything Iranians have seen before. The people of Iran are being massacred in unprecedented and historic numbers.”

The slaughter in the decade-long Syrian civil war was a laboratory for Iranian techniques of repression, he said, noting that Iranian leaders were often “disappointed when Bashar al-Assad was not violent enough against the people of Syria when they rose up.” In Syria, he said, the Iranians “honed their skills” of deadly repression and are now using them “against their own people on the streets of Iran.”

On the question of whether a U.S. attack on Iran could be averted by a change of heart by the regime, bringing them to the negotiating table, Javedanfar said he sees no chance of concessions unless Khamenei believes that “the Americans could kill him and his family.”

If the U.S. attacks and Iran retaliates against Israel, he noted, the Israeli military will quickly join in the attack.

“If the Iranian regime makes a mistake of attacking us, we have very genuine targets in Iran to attack, especially Iran’s missile program,” Javedanfar said, adding “I also hope Israel targets regime officials who are taking part in the oppression and suppression of the people of Iran in such a violent manner, I think that would hold Israel in very good stead in future history books of Iran.”