A positive demand shock for coltan, a mineral whose bulky output cannot be concealed, leads armed actors to create illicit customs and provide protection at coltan mines, where they settle as “stationary bandits.” A similar shock for gold, easy to conceal, leads to stationary bandits in the villages where income from gold is spent, where they introduce illicit mining visas, taxes, and administrations. Sanchez de la Sierra (2020) finds that having a stationary bandit from a militia or the Congolese army increases welfare. These findings suggest that armed actors may create “essential functions of a state” to better expropriate, which, depending on their goals, can increase welfare.