This paper addresses a recent wave of criticisms of liberal peacebuilding operations. We decompose the critics’ argument into two steps, one which offers a diagnosis of what goes wrong when things go wrong in peacebuilding operations, and a second, which argues on the basis of the first step that there is some deep principled flaw in the very idea of liberal peacebuilding. We show that the criticism launched in the argument’s first step is valid and important, but that the second step by no means follows. Drawing a connection between liberal peacebuilding and humanitarian intervention, we argue that the problems that the critics point to are in fact best addressed within the framework of liberal internationalism itself. Further, we argue that the development of the notion of human security marks a dawning awareness within liberal internationalism of the kinds of problems that the critics point to, however difficult it may still be to embody these ideas in practice.