Swearing on the Koran

Dennis Prager's piece arguing that members of Congress should not be able to swear their oath of office on the Koran has already been effectively refuted by Eugene Volokh. But I wanted to comment on one part of the piece. Prager writes:

Insofar as a member of Congress taking an oath to serve America and uphold its
values is concerned, America is interested in only one book, the Bible.

My question is, what is the "America" Prager refers to? Certainly a majority is Christian. But there are many millions of Americans who are not: Muslims, Jews, Hindus, Atheists and Agnostis, just to name a few. So, Prager is just wrong when he declares what "America" is interested in. "Many Americans," perhaps, but not "America."