This article explains cooperation problems between powerful democratic states and weak non-democratic states in the context of nuclear nonproliferation. Focusing on the interactions of the United States with North Korea, Iran, and Libya, it suggests that power asymmetry and information asymmetry foster mutual distrust by exacerbating two main strategic obstacles to cooperation: the time inconsistency of the stronger state's policy and the incomplete information regarding the non-democratic states. The nature of negotiations over nuclear weapons programs further exacerbates these problems. The overall implications of this article leave us pessimistic about the possibility of negotiated nuclear disarmament, but the theoretical analysis may help the negotiation strategy of the United States.