Threats to international peace and security include the proliferation of weapons of mass destructions, rogue nations, and international terrorism. The United States must respond to these challenges to its national security and to world stability by embracing new military technologies such as drones, autonomous robots, and cyber weapons. These weapons can provide more precise, less destructive means to coerce opponents to stop WMD proliferation, clamp down on terrorism, or end humanitarian disasters. Efforts to constrain new military technologies are not only doomed, but dangerous. Most weapons in themselves are not good or evil; their morality turns on the motives and purposes for the war itself. These new weapons can send a strong message without cause death or severe personal injury, and as a result can make war less, rather than more, destructive. Jeremy Rabkin is Professor of Law at George Mason University and was, for over two decades, a professor in the Department of Government at Cornell University. Professor Rabkin serves on the Board of Directors of the U.S. Institute of Peace, the Board of Academic Advisers of the American Enterprise Institute, and the Board of Directors of the Center for Individual Rights. John Yoo is Emanuel S. Heller Professor of Law at the University of California, Berkeley and a visiting scholar at the American Enterprise Institute. He served in the Bush administration Justice Department.