DEAL ISLAND, Md. — Deal Island is on the front lines of climate change. Even under the rosiest scenarios, much of the island will be underwater in a few generations. Still, climate change isn't a popular phrase here. In some sense, this island, a three-hour drive from Washington, is a microcosm of America today. This is Trump country, and many of those who live here are politically conservative and wary of outsiders or government restrictions on their way of life.