The 2017 Treaty on the Prohibition of Nuclear Weapons ( tpnw ) represents a daring act of self-empowerment: nuclear have-nots produced an international disarmament treaty without the involvement of the nuclear-weapon states or their allies. In this essay, we assess how the new treaty relates to the existing nuclear order and its four central norms: constraints on use, political restraint, non-proliferation, and disarmament. We discuss the tpnw 's origin in and impact on this contested order. At the heart of contestation are two security concepts: deterrence versus the immediate ban of nuclear arms, which result in fundamentally different ideas on how to pursue the road to “global zero.” Whether or not the tpnw and the Treaty on the Non-Proliferation of Nuclear Weapons are compatible depends on how the opponents handle their controversies. The key is to overcome the emotionalized polarization and rediscover a common basis in order to prevent damage to the existing nuclear order and bring forward nuclear disarmament in practice.