SecDef Addresses Army Association on North Korea as US Sends Bombers,Attack Sub to South Korea

A number of developments concerning the Korea crisis have unfolded over the past several days.On 7 October 2017,the Us Navy nuclear-powered attack submarine USS Tucson (SSN 770) arrived at US Fleet Activities Chinhae,Republic of Korea for a visit to bolster ties between the two allies.The Tucson can support a multitude of missions,the Navy said,including anti-submarine warfare;anti-surface ship warfare;strike;surveillance and reconnaissance.The boat has 12 vertical launch tubes for Tomahawk cruise missiles and four torpedo tubes.The Tucson was the twentieth of the improved Los Angeles-class attack submarines to be built.The Navy declined to disclose how long the Tucson would be in Chinhae;nor does it ever reveal whether its vessels are carrying nuclear weapons.*
On 9 October 2017,US Secretary of Defense Jim Mattis addressed the Association of the US Army on the status of the crisis on the Korean Peninsula:
It's right now a diplomatically-led,economic sanction-buttressed effort to turn North Korea off this path.And what does the future hold,neither you nor I can say;but there's one thing the US Army can do,and that is we've got to be ready to ensure we have military options that our president can employ if needed.
The international community has spoken (by imposing more sanctions on North Korea);but that means the US Army must stand ready.So if you're ready,that's your duty at this point in time.And I know the Army will always do its duty.*
On the evening of 10 October,the US launched two B-1B Lancer bombers,using Andersen Air Force Base,Guam,as a power projection platform,the US Air Force said.It was a sequenced bilateral mission in the vicinity of the Sea of Japan and East Sea with Republic of Korea  Air Force F-15J Slam Eagle fighter jets and Japanese Air Self-Defense Force Mitsubishi F-15 J Eagles.It enabled the operational units to improve their combined capabilities and tactical skills,while also building bilateral confidence and strong working relationships,according to Major Patrick Applegate of the 613th Air Operations Center at Joint Base Pearl Harbor-Hickham,Hawaii.Such joint night training hones the tactical prowess of each nation's aviators and is a clear demonstration of our ability to conduct seamless operations with all of our allies anytime,anywhere.It was the first time the US has staged joint night drills with both nations on the same night.*
The drills reportedly involved air to ground missile practice over the East Sea by the B-1Bs and the ROKAF F-15Ks,then a firing exercise with the JASDF F-15Js on the other side of the Korean Peninsula,over the Yellow Sea between South Korea and China.*