WASHINGTON – President-elect Joe Biden on Tuesday made his case for retired Army Gen. Lloyd Austin to be secretary of defense, urging Congress to waive a legal prohibition against a recently serving military officer running the Pentagon.With concern rising in Congress about maintaining civilian control of the military, Biden suggested he felt a need to counter an emerging narrative that Austin's nomination blurs the lines between civil and military roles.“Given the immense and urgent threats and challenges our nation faces, he should be confirmed swiftly,” Biden wrote in The Atlantic.