North Korea is "serious adversary": U.S.'s Gates

SEOUL (Reuters) - North Korea presents a serious security threat and U.S. forces in South Korea are ready to respond quickly and decisively to counter any attack, the U.S. defense secretary and military leaders said on Tuesday.

The United States has been trying to convince impoverished North Korea to abide by an international disarmament deal and scrap its nuclear arms program in exchange for aid and better global standing.