In this paper we propose to revisit two emblematic projects, Manhattan and Polaris, with the models developed by design theory. In particular we demonstrate, relying on recent advances in design theory, how these major projects, traditionally presented as radical innovations, are in fact quite different. We show that this explains the different managerial strategies of this two cases : whereas Polaris focuses on the control of the design process, Manhattan exhibit a very original strategy, characterized by the simultaneous exploration of different solutions, to manage unforeseeable uncertainties. We therefore hope to demonstrate the fruitfulness of the dialogue between design theory and project management.