Because North Korea had not conducted a successful test of a nuclear device, the extent of its nuclear weapons program remained ambiguous through 2005 and much of 2006. Though North Korea conducted numerous missile tests (some of which were branded failures by international experts), the question of whether they had actually mastered all aspects of nuclear weapons technology – ranging from material production to complex nuclear weapon design needed to produce the final detonation – remained unanswered. there was agreement in the U.S. intelligence community that North Korea could build a "modest" bomb with a yield of between 6 and 10 kilotons, but disagreement between Defense Intelligence Agency, CIA and the United States State Department over whether it could deploy a miniaturized warhead on a missile.