Amendment XIVSection 1. All persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States and of the State wherein they reside. No State shall make or enforce any law which shall abridge the privileges or immunities of citizens of the United States; nor shall any State deprive any person of life, liberty, or property, without due process of law; nor deny to any person within its jurisdiction the equal protection of the laws. With respect to a state religion you are correct. However, the "equal protection clause" does not make the 10th Amendment irrelevant. The left wants to make everything a matter for the federal courts, when clearly most of these issues are state issues, and the overwhelming majority are legislative rather than judicial issues.