In his new book, The Insurgents, Slate columnist Fred Kaplan tells the inside story of how Gen. David Petraeus and a small group of soldier-scholars revolutionized the U.S. military to fight small wars in cities and villages against insurgents and terrorists in the name of not only war, but also nation-building.

Think tanks such as RAND, Brookings, the Council on Foreign Relations and the Center for a New American Security all played a supporting role in that transformation, but perhaps none more than the American Enterprise Institute thanks to a special relationship between Petraeus and AEI fellow Fred Kagan and his wife Kimberly Kagan of the Institute for the Study of War.

In 2009, Kaplan writes, then-Secretary of Defense Robert Gates, also found himself surrounded by Kagans (308-309).

Gates knew the Kagan name. He remembered the slides from Fred’s briefing that called for a surge in Iraq. He knew of the book comparing American and European foreign policy by Fred’s brother, Robert. And Gates had long regarded their father, Donald, as one of the great military historians of all times. Once, after learning that Kimberly Kagan would be briefing him on developments in Baghdad, Gates turned to an aide and asked, “How many of these [f——] Kagans are there?”