President 
Donald Trump  warns the U.S. is “locked and loaded,” while Kim Jong Un’s regime says  it could launch missiles toward U.S. territory in the Pacific as soon as  next week.
Behind the scenes, however, it’s not clear that a  major military confrontation is imminent. Trump’s sharp rhetoric is  belied by the business-as-usual routines of the U.S. Defense Department,  which has been on stand-by for a belligerent act from North Korea for  decades. 
Secretary of Defense James Mattis continued with a  previously scheduled trip on the West Coast. Speaking to reporters in  California on Thursday, he said that while it’s his job to be ready with  military options, the U.S. is pursuing diplomacy. He praised last  weekend’s unanimous United Nations resolution tightening sanctions on  North Korea and said the U.S. “is gaining diplomatic results, and I want  to stay right there, right now.” A back-channel used earlier this year  to try to free an American held by Pyongyang is still active, according  to the Associated Press, though it isn’t clear those involved are  discussing the current crisis.
                                    Trump himself has sent some conflicting signals about what  would trigger a U.S. military response. He suggested Friday morning that  the U.S. isn’t looking to make a pre-emptive strike, saying on Twitter  that the military stood ready to act “should North Korea act unwisely.”  Speaking to reporters Friday afternoon in New Jersey, he said that if  Kim utters another “overt threat” or hits U.S. territory or allies he  will “regret it fast.”
The U.S. military says it is always  prepared for conflict on a moment’s notice. The motto of U.S. Army’s  Second Infantry Division, based in South Korea, is “ready to fight  tonight.” 
“There’s always some degree of readiness, but in the  face of these indications and warnings that North Korea is communicating  deliberately, we’re going to no doubt have an even higher condition of  readiness,” said Thomas Karako, a senior fellow at Center for Strategic  and International Studies in Washington.
                  For military analysts, who discount public saber-rattling,  there are several indicators to determine whether hostilities could be  around the corner:
Ship Deployments
The USS Ronald Reagan,  an aircraft carrier with more than 5,000 sailors that departed from its  home port in Japan in May, actually returned to port this week “after a  scheduled patrol to protect and defend the collective maritime  interests of the U.S. and its allies and partners in the  Indo-Asia-Pacific region,” according to ship’s Facebook page.
                  The Reagan had done exercises earlier this year with the USS  Carl Vinson aircraft carrier, which Trump briefly deployed to Korean  waters when tensions with Pyongyang ratcheted up earlier this year. The  Vinson, however, is now back in San Diego after a training exercise off  the California coast.
         <aside class="inline-newsletter" data-state="ready">                                                                                          Japan is home to as many as six U.S. Navy vessels  capable of defending against ballistic missiles, They are normally based  at Yokosuka, on the eastern side of Japan. Just moving those ships  toward the Korean peninsula would signal potential action to stop a  missile launch is more imminent and would likely be seen as an urgent  threat by Pyongyang. Asked about the ships’s current locations, the  Pentagon said it wouldn’t “discuss operational schedules.” 
</aside> 
Aircraft Deployments
Trump  on Friday tweeted out a series of photos of long-range B-1B bombers at  Andersen Air Force base in Guam, which North Korea has directly  threatened. The bombers have long been a key tool in the U.S. arsenal  for any renewed conflict in Korea, replacing B-52 stratofortress bombers  used in earlier decades.
“More aircraft deployments, particularly  bombers to Andersen in Guam and perhaps Hickam in Hawaii” would be sign  conflict is coming, said Rob Levinson, senior defense analyst with  Bloomberg Government.
The U.S. also maintains jet fighters,  including dozens of F-16s, at locations on the Korean peninsula, such as  Kunsan Air Base on the country’s west coast, in addition to more than a  hundred South Korean jets.
Personnel Departures
Preparations  for conflict would also likely involve the departure, on a voluntary or  mandatory basis, of family members of U.S. military and diplomatic  personnel. Such a move would send a clear signal that the U.S. sees  widespread conflict on the horizon, particularly because Seoul, the  nation’s capital and most populous city, is just 35 miles south of the  border separating the two countries.
“The canary in the coal mine  for this is the surreptitious or overt evacuation of American military  family members,” said Retired Army Major General Robert Scales, who  commanded units in Korea and is the author of “Scales on War: The Future  of America’s Military at Risk.” If that happens, “that tells you that  things are getting bad,” he added in an interview.
On the North  Korea side, if war were imminent, the government would probably  undertake civil defense exercises, including rehearsing measures to open  up underground tunnels and get Pyongyang’s elite to safer havens, as  well as ramped-up, live-fire military drills, Scales said. The  evacuation drills haven’t been seen in more than five years, he said.
And in South Korea, any sign the President Moon Jae-In is mobilizing army reserves would be “very, very serious,” said Scales.
“Until  you see something like this go down, this is all just chatter,” Scales  said. “You have to see something on the ground to believe that this is  serious.”