“It is unprofessional for historians to view the multifarious and complex motivations of millions of people over hundreds of years through a single prism, as for example the 1619 Project does in its attempt to view all American history solely through the monstrous story of slavery. Similarly, although more and more people believe in conspiracy theories, they do not make good history. If there is a choice between a conspiracy and a mess, the truth is usually the mess. Or a messed-up conspiracy.”