Tolerating is when others endorse their religion and being ok with it, government isn't supposed to endorse religion, but yes it is supposed to tolerate it.
Do you think it's constitutional for the Federal Building in Downtown Los Angeles to endorse ficus? How will the Kentucky Blue Grass feel? Yet they have ficus growing out front, clearly an endorsement of ficus over all other grass and the establishment of ficus as the official grass of the United States.....
It'd be a huge deal in this country if the government put up a bunch of muslim or hindu artifacts because we wouldn't want them to endorse those religions,
They already put up Islamic displays. It's only Christianity which is outlawed. You know this.
Wrong on the first count because that's not religion.
I have no idea what you're talking about on the second count, religious art at a museum? I've seen instances of all religion's art at those places.