The United States, we are told, is the most powerful nation in world history, the sole superpower, winner of the Cold War, the “indispensable nation,” a “hyperpower” that has achieved “full spectrum dominance” over all other military forces on Earth. Yet the US failed to achieve its objectives in Iraq and Afghanistan, was defeated outright in Vietnam, and since World War II has won unambiguous victories only in the first Gulf War of 1991, a war with the strictly limited objective of expelling Iraq from Kuwait, and in various “police actions” against pathetically small and weak opponents in the Dominican Republic in 1965, Grenada in 1983, and Panama in 1989. How can we explain this dichotomy between unparalleled military advantage over all rival powers and a virtually unblemished record of military defeat since the end of the Cold War? And how has the strange mix of great military capacity and inability to use that power to attain military victories affected America’s ability to maintain geopolitical hegemony?