Open this photo in gallery: People hold up signs as they protest the Trump administration outside City Hall, on March 4, in San Francisco.Godofredo A. Vásquez/The Associated Press As Donald Trump prepared Tuesday to address a joint session of Congress, protest groups gathered at parks, statehouses and other public grounds across the country to assail his presidency as dangerous and un-American. The rallies and marches – set in motion by the fledgling 50501 Movement, a volunteer-driven group organized in the weeks after Trump’s inauguration – mark the latest attempt at national resistance to the hardened support of Trump’s “Make America...