Abstract It has become almost commonplace to regard the concepts of Responsibility to Protect (R2P) and Just War as not only compatible but rather closely connected. Contrary to this position I argue here that some Just War criteria are in significant tension with R2P. This tension results from the fact that Just War only makes war permitted while R2P prescribes an obligation. But R2P and Just War not only are in significant tension, but also suffer from inverted weaknesses: R2P is (...) too demanding while Just War is not demanding enough. Granting that R2P implies a duty to protect, I argue that such a duty is too demanding since it conflicts with the principle of ?ought implies can?, whereas Just War is arguably not far-reaching enough as ?duties-talk? does not fit into its structure. I finish by proposing an interpretation of R2P and Just War which not only eliminates the tension but also compensates for these weaknesses. (shrink)