Since the end of World War Two, the Pentagon’s budget has increased and decreased, arriving at its current levels that rival past peaks and exceed average spending during the Cold War. Probing the budget data reveals controversies that are not always apparent. If the dollars are “adjusted for inflation,” who is doing the adjusting, and do they have an agenda? Is it appropriate to measure the actual dollars spent or their percentage of gross domestic product, and why does that matter? Why have US forces been shrinking and aging as the budget increases? Is the Department of Defense budget all that America spends for national security? How do our spending levels compare to what our potential opponents are spending? These questions constitute just some of the controversies that surround the defense budget. The Straus Military Reform Project has attempted to explain several of these arguments in the past; the materials presented here expand greatly on the issues.