National defense is the textbook example of a public good. In order to understand how economists present public goods to undergraduates, we analyze 50 texts from across three widely taught undergraduate economics courses: principles of economics, intermediate microeconomics, and public finance. We find that textbooks overwhelmingly present national defense as a public good and rarely mention the possibility of government failure. This leaves students with an incomplete and biased exposure to the government provision of public goods. We reconsider some of the main assumptions associated with the standard treatment of national defense as the quintessential public good and discuss opportunities for educators to better prepare students as economists and citizens.