Offensive realism and defensive realism are variants of structural realism. They share the basic beliefs of survivalism, statism (state as the primary unit), self-help and anarchy. (See international relations theory.) However, contrary to defensive realism, offensive realism regards states as aggressive power maximizers and not as security maximizers. According to John Mearsheimer, "Uncertainty about the intentions of other states is unavoidable, which means that states can never be sure that other states do not have offensive intentions to go along with their offensive capabilities". According to Mearsheimer, though achieving hegemony by any state is not likely in today's international system, there is no such thing as a status quo and "the world is condemned to perpetual great power competition".