I don't agree. The founding fathers intent on Seperation of Church and State was to not provide sanctioned government powers to any religious institution or religious point of view. It was not intended to exclude religion from the public sphere, in fact quite the opposite is true. The founding fathers wanted religion to prosper in the public sphere and they were remarkably succesful. The US has one of the highest Church attendtence rates in the industrialized world and we have one of the largest diversities of religions of any nation.
The founding fathers primary concern with religion and government was the corrupting influence one has upon the other and vice versa. Thus they wanted no official government sanction for any religion or religious institution but gave them otherwise a freehand in our public life. We very much need religion in our public life, we just don't need it in our government or the official public policy of our government. In fact look at the history of totalitarian States like Nazi Germany and the Soviet Empire. One of the first things they did was to strictly limit Religions public role or got rid of it all together.