Not everyone is agreed that the monument on stone mountain is a good idea, we don't even have unanimous approval of the Crazy Horse carving.
But suppose the US became mostly Muslim, why would we keep Mt. Rushmore?
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I thought Stone Mountain was probably a waste of money at the time it was built, but the site is an interesting place to visit, and I certainly would not favor tearing it down.
Most pf the French people are nonbelievers, but I doubt that there is even ΒΌ% of the French that would tolerate tearing down Notre Dame or Montremarte Basilica. The US will never be "mostly Muslim", but even if it were, I don't think a majority of the people would want to tear it down. Syria, Turkey, Jordan, Egypt and Libya are full of buildings made by Greeks, Romans and Christians, and there is no movement to destroy them, because they are part of the ancestral heritage.
The Pyramids and the Sphinx are major tourist attractions, and tourism is one of Egypt's major industries.No way they will destroy them. Egyptians do indeed strongly identify with the ancients, at least the ones I know.