Following the invasion of Iraq in 2003, Coalition forces discovered that the military, security, and intelligence agencies of Iraq were well suited to transition into an insurgency after conventional defensive measures had failed. This paper argues that this is the habitual norm for repressive totalitarian regimes when faced with invasion. This paper examines existing counterinsurgency theories, and then uses the case study method to compare the Werwolf movement in 1945-46 Nazi Germany, the partisan resistance movement in the 1941-44 Soviet Union, and the ongoing Iraqi insurgency. It compares how these movements were planned, organized, manned, and executed. It examines the three insurgencies for common threads and themes. The conclusions of this paper are that repressive regimes are well suited to defend themselves through post-hostility guerrilla movements, and the decision to do so is common. The success or failure of such decisions is a function of several factors. These are the speed and strength of the occupying force, the ability of the defeated government's survivors to demonstrate unity of effort, and adequate time and safe areas for the regime survivors to rally and organize. Military planners should expect such movements as a likely outcome of victory and plan accordingly. Defeating such insurgencies is intensive in terms of time, troop commitment, and resources, however. Regardless of its prowess in fighting in high-intensity conflicts, the US military should expect to execute counterinsurgency operations as part of future expeditionary operations.