"This is reminiscent of the Holocaust," said Rabbi Marvin Hier, the dean of the Simon Wiesenthal Center in Los Angeles. "Iran is moving closer and closer to the ideology of the Nazis."

The first world leader to require Jews to wear distinctive badges (a yellow belt and a yellow conical "dunce" cap) was Haroun al-Rashid, the Abbasid caliph, who ruled in Baghdad in the era of Charlemagne, the late 700s and early 800s.

Haroun's idea was later copied by the popes, but long after it vanished from the Christian world it endured in Islamic countries. Even in our own time, one of the final acts of the Taliban in Afghanistan was to attempt to enforce a distinctive badge on that country's Hindu minority.