This Article examines the use of federal tax provisions to effect changes in state law corporate governance. There is a growing academic controversy over these provisions, fueled in part by their popularity among legislators as a method of addressing the recent spate of corporate scandals. As a case study on the use of tax to regulate corporate governance, this paper compares and contrasts two measures enacted during the New Deal-the enactment of the undistributed profits tax in 1936 and the overhaul of the tax-free reorganization provisions in 1934-and considers why the former was so much more controversial and less sustainable than the latter. While some of the difference can be explained by the different political and economic circumstances surrounding each proposal, this Article argues that the divergence in the degree of opposition can be explained in part by an examination of the extent to which each provision threatened an underlying norm, or longstanding standard, of corporate behavior. The Article goes on to test this norms-based explanation against several recent attempts to enact corporate governance-oriented tax provisions and concludes that it has modern relevance. The implication is that while Congress may use the Tax Code to reinforce existing norms of corporate behavior, it is likely to be less successful when it tries to use the Code to change existing norms or introduce new ones.