Homeland Security Secretary Alejandro Mayorkas on Sunday rebuffed calls from leading Republicans to step aside — or risk impeachment — and underscored the critical nature of managing migration challenges “gripping” the Western Hemisphere. “I’m proud to do it alongside 250,000 incredibly dedicated and talented individuals in the Department of Homeland Security, and I’m going to continue to do my work,” he said. “It’s gripping the hemisphere and a regional challenge requires a regional solution.”