You are correct. The U.S. Government doesn't endorse a religion. And right there is where the FF's intended the words "Congress shall pass no law..." to end in regards to the 1st Amendment.
It wasn't intended for what the anti Religion zealots have turned it into.
Again, I agree. The anti-theists and militant minority religions have gone way too far with this issue. Just remember, there are more anti-theists than there are atheists. Atheists don't really care all too much. It's the militant ones, the anti-theists, that cause the issues.
“A creative man is motivated by the desire to achieve, not by the desire to beat others.” – Ayn Rand