The research of strategic culture typically follows its permanent features, largely ignoring the possibility of abrupt shifts thereof. The article overcomes this deficiency by proposing a framework for analysing change in strategic culture, presuming a crucial role played by pre-existing strategic subcultures. The utility and limits of the new approach are then tested on the U.S. strategic culture after 2001, focusing specifically on the rise of counterinsurgency in connection to the wars in Iraq and Afghanistan.