well? is it or isn't it?

I have to disagree. It's a RELIGIOUS nation.

It’s a secular nation established by various groups of Christians.

which religion is dominant? should they have more influence? what about the atheists? do they have the right to determine the religiosity of the nation?

This is only a slice of the 4k+ religions. The US doesn't have a designated religion, nor ethnicity, nor language. It's a melting pot. A common misconception in "in God we trust" is that they meant the Christian God. When I was looking into joining the free masons, they tought me that I don't have to believe in that god, but any god. But seeing that the majority is religious, that's my argument it's religious.

i think some people answer what religion they were born into and leave it at that. that's an easy cop out that hides a much larger number of non-believers who simply don't think it much.

I was raised Nazareth. But have grown my own opinions on the matters.

It was founded on principles of religous freedom.

That doesn’t change that it was founded by Christians and identified as Christian