In the general debate prior to the onset of war in Iraq, we made public our view, in a letter to the Guardian newspaper, that the war could be justified neither by reference to earlier UN Security Council resolutions nor by way of the doctrine of self-defence. In this article we reflect on some of the anxieties we experienced both before and after that ‘intervention’ in terms of the vision of international law we might unwillingly promote, and in terms of the role we appeared to assume for ourselves, and our professional colleagues, in public debate. Despite our efforts to prevent legal issues from dominating, we came to be viewed as the defenders of an anti-hegemonic legality – resisting the erosion by an opportunistic coalition of the principles of sovereignty, non-intervention, and collective security. We were concerned that this made us appear champions of international law in a way with which none of us was entirely comfortable. On the other hand, in contesting that, we seemed in danger of valorising a politics of expertise that gave international lawyers a privileged position within the debate. We reflect, then, on the consequences, intentional or otherwise, of our intervention, and explore the dilemmas associated with it. The problem with which we finally grapple is whether the relationship between critical scholarship and the techniques associated with it (anti-formalism, complexity, and indeterminacy) is such as to preclude strategic intervention in the effort to stop a war.