The road from Maryland’s statehouse to the nation’s capital is a relatively short 30 miles, but for all the difference between Annapolis and Washington, the two cities could be 30 light-years away. Maryland is routinely deemed one of the nation’s better-governed states, its social safety net earning praise for protecting citizens during the coronavirus pandemic. Washington has passed from partisan division to a more advanced stage of political combat, in which progressives are fighting Democrats, conservatives are fighting Republicans and President Trump sends everyone into disarray. Larry Hogan, the Republican governor of Maryland, arrived in Washington with a simple message:...