After the Eichmann trial in 1961 (witnessed by Birnbaum in Jerusalem) people had become increasingly aware of the horrors of the Holocaust, so the Columbia meeting proved emotional and there was a call for action. Birnbaum proposed a protest rally outside the Soviet UN Mission on the Soviet May Day holiday, only 4 days later. He mobilized his Yeshiva University core, contacted other campuses, and some 1,000 students showed up, getting excellent media publicity. According to the Center for Jewish History, this May Day rally marked the commencement of public confrontation with the Kremlin and the initiation of the national movement for Soviet Jewry. Thereafter, four other Soviet Jewry pioneers, Dr. Moshe Decter, Professor Abraham Joshua Heschel, Israeli diplomat Dr. Meir Rosenne, and Dr. Louis Rosenblum of Cleveland (later founding Chairman of the Union of Councils for Soviet Jews), were delighted to support Birnbaum's initiatives.