The defense chiefs of the United States and South Korea on Thursday warned North Korea that any nuclear attack against them by Pyongyang would "result in the end" of leader Kim Jong Un's regime as concerns grow over the isolated country's unprecedented pace of weapons tests this year.U.S. Defense Secretary Lloyd Austin also pledged to respond to any North Korean provocation by employing nuclear-capable U.S. strategic assets "to the level equivalent to constant deployment," South Korean Defense Minister Lee Jong Sup said at a joint press conference with Austin following their security consul…READ FULL ARTICLE