Though Chain cared deeply about Eretz Yisrael and was by many accounts leaning toward accepting Weizmann’s offer, he had great difficulty balancing his Zionism against the best interests of the future of antibiotics and his decision to reject the offer was ultimately made by a combination of the Arab armies’ invasion of Israel in May 1948 and an attractive offer to work at the Superior Institute of Health in Rome.
Chain believed that advancing the development of penicillin, and curing diseases that were the scourge of the entire human race, were ultimately more important and could not effectively be pursued in Israel, a country beset by war.
Nonetheless, he continued his strong support of Israel in general, remaining active in Jewish organizations and in Israeli institutions of higher education, and of the Weizmann Institute in particular, serving as a member of its Board of Governors. He also received honorary degrees from Yeshiva University (1948) and from the Albert Einstein College of Medicine (1961).
