In between her stints of service in the Pentagon, first under U.S. President Barack Obama and now under President Joe Biden, Karlin explored what went wrong with the two big U.S. wars of this century, in Afghanistan and Iraq. She considered, in turn, how the military went to war, how it waged war, who served in the ranks, and who led, before addressing what the prosecution of these wars meant for future conflicts. To this end, she interviewed around 100 civilian and military figures. Quotes from these interviews enliven her book and help bring home the importance of personalities, leadership, the emotions that can be aroused by apparently dry debates about civil-military relations, and the dangers of too great a separation between the armed forces and the society they serve. Americans routinely express gratitude for soldiers without really understanding what their service entails or the toll of long tours in hostile environments. She urges continued reflection on mistakes as well as achievements, better dialogue between the civilian and military leadership, and holding them both to proper account.