The debate over marijuana legalization is just one of the many ways the political landscape is changing as the US comes to terms with drug and criminal justice policies that many experts and Americans consider to have failed at a great cost to the nation’s liberty and finances. The war on marijuana in particular has cost the US billions of dollars over decades, led to a black market for pot that criminal organizations use to fund violent operations, and contributed to the explosive growth of America’s incarcerated population, which is now the largest in the world. And despite those costs,...