U.S. National Intelligence Director James Clapper on Tuesday warned North Korea's "bellicose rhetoric," while "propaganda-laced," may be an "indicator of their attitude."
Clapper was speaking in a hearing of the U.S. Senate Intelligence Committee. He added he is "very concerned about the actions of the new young leader" Kim Jong-un.
He recalled the North's sinking of the South Korean Navy corvette Cheonan and shelling of Yeonpyeong Island, adding that the North Korean army is well prepared to launch a limited attack without prior warning.
He added the North displayed "what appeared to be a road-mobile intercontinental ballistic missile" during a parade last year.
"North Korea has already demonstrated capabilities that threaten the United States and the security environment in East Asia," Clapper said. "We believe North Korea has already taken initial steps towards fielding this system, although it remains untested."
"The Intelligence community has long assessed that, in Pyongyang's view, its nuclear capabilities are intended for deterrence, international prestige and coercive diplomacy. [But] we do not know Pyongyang's nuclear doctrine or employment concepts," Clapper said. "Although we assess with low confidence that the North would only attempt to use nuclear weapons against U.S. forces or allies to preserve the Kim regime, we do not know what would constitute, from the North's perspective, crossing that threshold."
Clapper also expressed worries about proliferation of nuclear weapons and missiles. He said the regime's exports of ballistic missiles and components to Iran and Syria and its support of a Syrian nuclear reactor bombed by Israel in 2007, are good examples of its proliferation activities.
The U.S. is wary that the regime will renege on its promise in the six-party denuclearization talks not to transfer nuclear materials and technology to a third country, he added.