In a recent Facebook discussion, someone asserted that as long as we consider being Christians more important than being Americans, then our nationalism isn’t idolatrous. But it’s not that simple.
In the Bible, we find that the Israelites struggled with polytheism throughout the Old Testament. It wasn’t so much an outright rejection of Yahweh; it was a desire to worship Yahweh along with other gods. Or to make images to worship and call them Yahweh.