The Pentagon has told National Guardsmen deployed to the nation’s capital not to use firearms or ammunition, and has issued orders to send home active-duty troops that the Trump administration amassed outside the city in recent days, a sign of de-escalation in the federal response to protests in the city. Defense Secretary Mark T. Esper made the decision to disarm the guard without consulting the White House, after President Trump ordered a militarized show of force on the streets of Washington to quell demonstrations that were punctured by an episode of looting Sunday, two senior administration officials said. Trump had...