mhpine,

 I think you are underestimating the change that alternatives to a specific belief in active God does to religion. Even recently, the fight between the Modern Orthodox and the ultra-Orthodox over Slifkin was the first massive overt traditional Jewish retaliation to the haredim in decades. Evolution and other related theories all challenging Creationism have harmed religious commitment more than social issues and challenges. Even 19th century ideas such as Marxism are all tied directly to rejection of an active God.