Early on Friday morning, vast swathes of the red-rock high plateau that surrounds federally protected buttes in southern Utah were officially thrown open to miners. A controversial decision weeks earlier by President Donald Trump had shrunk the size of two national monuments — known as Bears Ears and Grand Staircase-Escalante — by hundreds of thousands of acres, enraging environmentalists and American Indian groups who feared a stampede of mine and oil wildcatters would rush in and destroy the area’s sandstone vistas, historic rock carvings and artifacts.