WASHINGTON - He called on the country to come together. He warned of pain to come. And he deferred to the nation’s public health experts while at least momentarily putting aside petty squabbling. After weeks of trying to play down the risk posed by the coronavirus pandemic, President Donald Trump struck a new, more urgent tone on Monday as he delivered a sobering message to Americans grappling with a new reality that will dramatically alter their lives for months to come. Trump’s more somber tone came as he addressed the public at a White House briefing and made a direct...