duration of the assignment. Such assignment, in itself, does not change the specified command to a unified command. If, however, the assignment is major and of long duration, a unified command is  normally  established  instead  of  a  specified command. The  commander  of  a  specified  command  has the  same  responsibilities  as  the  commander of  a  unified  command;  however,  the  specified commander cannot establish subordinate unified commands. The only specified commands in existence at the  time  of  this  writing  are  the  Strategic  Air Command (SAC) and the U.S. Forces Command (USFORCOM). DEPARTMENT  OF  THE  ARMY The primary responsibility of the Department of  the  Army  is  to  prepare  land  forces,  as necessary, for war. The Department of the Army is  also  responsible  for  expansion  of  peacetime components  of  the  Army  to  meet  the  needs  of war. The Army includes land combat and service forces  and  aviation  and  water  transport. MISSION The  mission  of  the  Department  of  the  Army is  to  organize,  train,  and  equip  active-duty  and Reserve   forces   for   the   preservation   of   peace, security,   and   the   defense   of   our   nation.   The Army’s  mission  focuses  on  land  operations;  its soldiers must be trained with modern arms and equipment  and  be  ready  to  respond  quickly. FUNCTION The following are the primary functions of the Department  of  the  Army: To  organize,  train,  and  equip  forces for  the  conduct  of  prompt  and  sustained combat  operations  on  land—specifically, forces to defeat enemy land forces and to seize,  occupy,  and  defend  land  areas To   organize,   train,   equip,   and   provide Army  air  defense  units  as  required  to defend the United States against air attack To   organize,   train,   equip,   and   provide Army  forces,  in  coordination  with  the other  services,  for  joint  amphibious  and airborne  operations • • • • • • To   develop,   in   coordination   with   other U.S.  military  services,  doctrines,  tactics, techniques,  and  equipment  for  amphibious operations To   organize,   train,   equip,   and   provide forces  for  the  support  and  conduct  of special  operations To   develop,   in   coordination   with   other U.S.   military   services,   doctrines,   pro- cedures,   and   equipment   employed   by Army   and   Marine   forces   in   airborne operations To   provide   forces   to   occupy   territories abroad  and  establish  a  military  govern- ment pending the transfer of this respon- sibility  to  other  authority To   perform   functions   relating   to   the management  and  operation  of  the  Panama Canal To  perform  projects  for  improvement  of navigation,  flood  control,  beach  erosion control, and other water resource develop- ment in the United States, its territories, and its possessions DEPARTMENT  OF  THE  AIR  FORCE The primary responsibility of the Department of  the  Air  Force  is  to  prepare  the  Air  Force,  as necessary, for war. It is also responsible for the expansion  of  peacetime  components  of  the  Air Force  to  meet  the  needs  of  war.  The  Air  Force, within the Department of the Air Force, includes both  combat  and  service  aviation  forces. MISSION The  mission  of  the  Air  Force  is  to  preserve, in  conjunction  with  the  other  armed  forces,  the peace  and  security  of  the  United  States  by providing   air-combat,   air-service,   aerospace, missile,  and  airlift  forces. FUNCTION The  primary  functions  of  the  Air  Force  are as  follows: • To  organize,  train,  and  equip  Air  Force personnel  to  conduct  prompt  and  sustained combat operations in the air. Specifically, the  Air  Force  defends  the  United  States 11-8