give your definition of secular?
here is the one I found and think it describes our country the best
: not bound by monastic vows or rules; specifically : of, relating to, or forming clergy not belonging to a religious order or congregation
but religious people, even priests themselves can't be precluded from serving in the government (and used to serve in the past) - it would be in violation of the no religious test claw...
but what it means is that the government (elected by people) doesn't take orders from any (unelected) church, but people with religious views and convictions are still free to serve in the government...I hope you see the difference...(sr)