MarkWhittington writes: One of the more substantive issues that was discussed during the Republican presidential debate in Detroit concerned the latest threat to come out of North Korea. That country's mad, bad, and dangerous to know leader Kim Jong-Un has ordered his nuclear arsenal prepared and is firing missiles in the vicinity of Japan. The United States and South Korea have started military maneuvers, partly as a result of North Korea's actions. Discussions on deploying the Terminal High Altitude Area Defense (THAAD) system in South Korea have also become urgent. Sen Ted Cruz, R-Texas would go one step further. He proposed reviving the idea of space-based missile defenses that were part of the Reagan-era Strategic Defense Initiative.