(JTA) — One of the six men with the power to substantially change the direction of the United States Postal Service is a Jewish businessman who says his support for organized labor was heavily influenced by his socialist Zionist summer camp.

Ron Bloom, who steered the nation’s automobile industry through its own crisis a decade ago and now works in private equity, was appointed to the mail service’s board of governors last year. One of two Democrats on the board, his term ends in December.

Bloom told the Jewish Telegraphic Agency in 2009 after becoming Obama’s “car czar” that his upbringing in...