This article reviews the claim that economic policymakers in the post-COVID UK should learn the lessons of the 1940s. Post-1945 policies relating to delivering full employment, levelling up, upgrading social security, dealing with the public debt legacy, and addressing the productivity puzzle are considered. The article finds many reasons to criticise the policies of the 1940s. Although, superficially, outcomes look good, a closer examination reveals significant failings notably concerning design of the welfare state and supply-side policy for growth. The 1940s do not provide a good way to address the productivity slowdown or twentyfirst-century social insurance.