[4] Rackman entered service during World War II in the United States Army Air Forces in 1943 as a chaplain.

He served as a military aide to the European Theater of Operations special adviser on Jewish affairs, where his experiences with survivors of the Holocaust influenced his decision to pursue the rabbinate.

[4] In the 1950s, the United States Air Force Reserve denied Rabbi Rackman's security clearance, citing him as a "bad risk".

In a 1977 profile in The New York Times, Rackman cited his opposition to the death penalty for Julius and Ethel Rosenberg and his support for Paul Robeson as factors behind the decision.

Offered the opportunity to resign or face a military tribunal, the Rabbi chose a court martial, where he was acquitted and was shortly thereafter promoted from major to lieutenant colonel.

[9] After a trip to Eastern Europe and the Soviet Union in 1956 as part of a group from the Rabbinical Council of America, Rackman was part of a group of New York-area Rabbis who reported that their experience "leads us to the melancholy conclusion that Judaism in Russia is seriously threatened with extinction", despite improvements in the preceding years for Soviet Jewry.

Criticism came from across the Orthodox spectrum, with the Haredi Agudath Israel of America calling the court's halachic basis "spurious" and British Chief Rabbi Jonathan Sacks claiming that Rackman's solution exacerbated the problem it was trying to solve.