"We have to give power back to the police,” Donald Trump proclaimed during his campaign, and earlier this year he delivered … or so he thinks. The early weeks of Trump’s presidency indeed match his campaign rhetoric, replete with an executive order seeking to make assault against police officers a federal crime. Americans are understandably divided by Trump’s “law and order” approach to policing reform. Research suggests Americans’ reactions to Trump’s policies will be shaped both by their own experiences with police and by their moral predispositions. It starts with race. Anyone discussing...