Jewish identity became cultural and secular as it merged with American identity

Evidence

A growing number of Jews blended their religious identity into their American national identity as their communal activities mirrored those of their Christian neighbors’ church activities. Starting in the 1920s, attendance at religious services and consumption of Kosher meat began to decline. With each passing decade, Jewish identity became increasingly more cultural and secularized and less religious. — Sahar F. Aziz, The Racial Muslim, 445