There never was any such thing as "separation of church and state". I defy you or anyone to show it to me in the Constitution.
"Thomas Jefferson wrote that the First amendment created a wall of separation between the church and the state. James Madison said it "drew a line," but it is Jefferson's term that sticks with us today. The phrase is commonly thought to mean that the government should not establish, support, or otherwise involve itself in any religion." (Pat Roche)
Here is the first line of the First amendment to the U.S. Constitution. "Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof;"
Plain and simple, that is all it says. There is no mention of separation of church and state other than Jefferson saying something similar to that. In reality, the amendment was to prevent the government from making The Church of England the religion of the new USA. Since almost everyone belonged to that church at the time, and we had just separated ourselves from England, we didn't want anyone pushing England's church down our throat.