MARS has changed its name slightly to "Military Auxiliary Radio System." Also, the US Navy/Marine Corps MARS will not be closing down.
From ARRL:
On Wednesday, December 23, the Department of Defense (DoD) issued an Instruction concerning MARS, effective immediately. This Instruction gives the three MARS services -- Army, Air Force and Navy/Marine Corps -- a new focus on homeland security and a new name: Military Auxiliary Radio System. The Instruction is the first major revision to MARS since January 26, 1988 -- as such, the first revision since the 9/11 attacks and Hurricane Katrina, two major events that changed the way Amateur Radio dealt with emergency communications.
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In the past, MARS had focused primarily on emergency communications and health and welfare support. The DoD's Instruction now directs the three MARS services to provide "contingency radio communications" to support US government operations, DoD components and "civil authorities at all levels," providing for national security and emergency preparedness events. MARS units will still continue to provide health and welfare communications support "to military members, civilian employees and contractors of DoD Components, and civil agency employees and contractors, when in remote or isolated areas, in contingencies or whenever appropriate." MARS must also be capable of operation in "radio only" modes -- without landlines or the Internet -- and sustainable on emergency power (when public utility power has failed); some MARS stations must be transportable for timely deployment.
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This revision -- which was years in the making -- keeps the Navy/Marine Corps MARS intact; until now, members of this MARS service were concerned that their part of MARS might be terminated by Navy commanders.
Full story is here.