30 What is the "Bush Doctrine"? O theory that the U.S. must lead an international alliance in War on Terror O theory that the U.S. Missile Shield must be built and extended to also protect Europe Otheory that the U.S. military must be strong enough to fight and win a major war and a regional/local war at the same time theory that the U.S. is justified in waging preventive war" in order to protect itself