For years, talk of developing, let alone using, offensive weapons in space was taboo in U.S. military circles. Although the U.S. was the first to demonstrate destructive power in space, official policy made clear such capabilities were for defensive purposes only, given the long-lasting effects of debris in orbit and the U.S. commitment to keeping space a peaceful domain. But as China and Russia have tested anti-satellite (ASAT) weapons and built up rival space capabilities designed to counter U.S. advantages in the heavens, those basic premises have changed.