But the national government under the U.S. Constitution is prevented by clear and bold language from any power to control religion. Even the Preamble lacks the common reference to God which is even found in most current state constitutions. This study of state constitutions in the founding period reveals both a wide variety of provisions concerning religion and a quick turnover of these clauses when constitutions were modified. It is important to keep in mind that disestablishment was a process. Writing a clause or provision into a constitution, or passing statutes does not automatically bring about change.
Humans are creatures of habit and thus tend to continue to do things in the same ways.
Disestablishment, the separation of church and state producing religious freedom, would not take place over night. As already demonstrated here, it was a process, one that began on the state level in 1776, and moved forward over a period of time. That process still takes place today. The events on the state level influenced what took place on the national level, which in turn helped reinforce and further influence what was taking place on the state level. The Establishment Clause, Religion and the First Amendment, By Leonard W Levy, page 146-147.