Cutting to the chase, I’d just like to point out that the 1st Amendment protects the right of freedom of religion, and religion, by definition, includes God.
Therefore, atheism is not the subject matter of the 1st Amendment. The rejection of God is NOT a “form” of religion. In fact, concerning the 1st Amendment, atheism is literally irrelevent.
A very common straw man argument on FR.
For every atheist of that stripe, there are a dozen more for whom the supernatural is just a concept they don't entertain.
I'm in that group and have no problem interacting with any believers, or with respecting their beliefs.
These are preachers recruiting for the church of materialism. Libertarians should take their own advice and mind their own business while leaving people to their own business. If there were to be a “clash” in this country, given the numbers, atheists would be dead, dead, dead.