The bruhaha over whether a new Congressperson swears on a Christian Bible or a Koran seems remarkably stupid. Swearing in is about taking an oath, an oath to truthfulness, honesty, and whatever else. The Bible is not a stand-in for the beliefs of the country at large, it is representative of what the oathtaker believes is a significant and binding power. This is why, in courts, people are allowed to swear by whatever they consider holy/binding. An atheist could swear on their honor if that was appropriate. The book or document isn't the important thing; the swearing itself is the important aspect.

Does anyone still teach civics anymore? The USA is a pluralistic society; get used to it. People have different value systems and the Christian Bible is just a book to some people.