 It was envisioned that the Royal Australian Navy maintaining a fleet that would include two light fleet carriers , two cruisers , six destroyers , 16 others ships in commission and another 52 in reserved . The Royal Australian Air Force would have a strength of 16 squadrons , including four manned by the Citizen Air Force . Meanwhile , in a significant departure from previous Australian defence policy which had previously relied on citizen forces , the Australian Army would include a permanent field force of 19 @,@ 000 regulars organised into a brigade of three infantry battalions with armoured support , serving alongside a part @-@ time force of 50 @,@ 000 men in the Citizen Military Forces . The Australian Regular Army was subsequently formed on 30 September 1947 , while the CMF was re @-@ raised on 1 July 1948 .   = = = Occupation of Japan , 1946 – 52 = = =   In the immediate post @-@ war period Australia contributed significant forces to the Allied occupation of Japan as part of the British Commonwealth Occupation Force ( BCOF ) , which included forces from Australia , Britain , India and New Zealand . At its height in 1946 the Australian component consisted of an infantry brigade , four warships and three fighter squadrons , totalling 13 @,@ 500 personnel . The Australian Army component initially consisted of the 34th Brigade which arrived in Japan in February 1946 and was based in Hiroshima Prefecture . The three infantry battalions raised for occupation duties were designated the 1st , 2nd and 3rd battalions of the Royal Australian Regiment in 1949 , and the 34th Brigade became the 1st Brigade when it returned to Australia in December 1948 , forming the basis of the post @-@ war Regular Army . From that time the Australian Army contribution to the occupation of Japan was reduced to a single under @-@ strength battalion . Australian forces remained until September 1951 when the BCOF ceased operations , although by the time the majority of units had been committed to the fighting on the Korean peninsular following the outbreak of the Korean War in 1950 . The RAAF component consisted of Nos. 76 , 77 and 82 Squadrons as part of No. 81 Wing RAAF flying P @-@ 51 Mustangs , initially based at Bofu from March 1946 , before transferring to Iwakuni in 1948 . However , by 1950 only No. 77 Squadron remained in Japan . A total of ten RAN warships served in Japan during this period , including HMA Ships Australia , Hobart , Shropshire , Arunta , Bataan , Culgoa , Murchison , Shoalhaven , Quadrant and Quiberon , while HMAS Ships Manoora , Westralia and Kanimbla also provided support .   = = Cold War = =   = = = Early planning and commitments = = =   During the early years of the Cold War , Australian defence planning assumed that in the event of the outbreak of a global war between the Western world and Eastern bloc countries it would need to contribute forces under collective security arrangements as part of the United Nations , or a coalition led by either the United States or Britain . The Middle East was considered the most likely area of operations for Australian forces , where they would most likely operate with British forces . Early commitments included the involvement of RAAF aircrew during the Berlin Airlift in 1948 – 49 and the deployment of No. 78 Wing RAAF to Malta in the Mediterranean from 1952 to 1954 . Meanwhile , defence preparedness initiatives included the introduction of a National Service Scheme in 1951 to provide manpower for the citizen forces of the Army , RAAF and RAN .   = = = Korean War , 1950 – 53 = = =   On 25 June 1950 , the North Korean Army ( KPA ) crossed the border into South Korea and advanced for the capital Seoul , which fell in less than a week . North Korean forces continued toward the port of Pusan and two days later the United States offered its assistance to South Korea . In response the United Nations Security Council requested members to assist in repelling the North Korean attack . Australia initially contributed P @-@ 51 Mustang fighter @-@ bomber aircraft from No. 77 Squadron RAAF and infantry from the 3rd Battalion , Royal Australian Regiment ( 3 RAR ) , both of which were stationed in Japan as part of the BCOF . In addition , it provided the majority of supply and support personnel to the British Commonwealth Forces Korea . The RAN frigate HMAS Shoalhaven , and the destroyer HMAS Bataan , were also committed . Later , an aircraft carrier strike group aboard HMAS Sydney was added to the force .   By the time 3 RAR arrived in Pusan on 28 September , the North Koreans were in retreat following the Inchon landings . As a part of the invasion force under the UN Supreme Commander , General Douglas MacArthur , the battalion moved north and was involved in its first major action at Battle of Yongju near Pyongyang on 22 October , before advancing towards the Yalu River . Further successful actions followed at Kujin
ĠIt Ġwas Ġenvisioned Ġthat Ġthe ĠRoyal ĠAustralian ĠNavy Ġmaintaining Ġa Ġfleet Ġthat Ġwould Ġinclude Ġtwo Ġlight Ġfleet Ġcarriers Ġ, Ġtwo Ġcru isers Ġ, Ġsix Ġdestroy ers Ġ, Ġ16 Ġothers Ġships Ġin Ġcommission Ġand Ġanother Ġ52 Ġin Ġreserved Ġ. ĠThe ĠRoyal ĠAustralian ĠAir ĠForce Ġwould Ġhave Ġa Ġstrength Ġof Ġ16 Ġsquad rons Ġ, Ġincluding Ġfour Ġmanned Ġby Ġthe ĠCitizen ĠAir ĠForce Ġ. ĠMeanwhile Ġ, Ġin Ġa Ġsignificant Ġdeparture Ġfrom Ġprevious ĠAustralian Ġdefence Ġpolicy Ġwhich Ġhad Ġpreviously Ġrelied Ġon Ġcitizen Ġforces Ġ, Ġthe ĠAustralian ĠArmy Ġwould Ġinclude Ġa Ġpermanent Ġfield Ġforce Ġof Ġ19 Ġ@ , @ Ġ000 Ġregulars Ġorganised Ġinto Ġa Ġbrigade Ġof Ġthree Ġinfantry Ġbatt alions Ġwith Ġarmoured Ġsupport Ġ, Ġserving Ġalongside Ġa Ġpart Ġ@ - @ Ġtime Ġforce Ġof Ġ50 Ġ@ , @ Ġ000 Ġmen Ġin Ġthe ĠCitizen ĠMilitary ĠForces Ġ. ĠThe ĠAustralian ĠRegular ĠArmy Ġwas Ġsubsequently Ġformed Ġon Ġ30 ĠSeptember Ġ1947 Ġ, Ġwhile Ġthe ĠCM F Ġwas Ġre Ġ@ - @ Ġraised Ġon Ġ1 ĠJuly Ġ1948 Ġ. Ġ Ġ Ġ= Ġ= Ġ= ĠOccup ation Ġof ĠJapan Ġ, Ġ1946 ĠâĢĵ Ġ52 Ġ= Ġ= Ġ= Ġ Ġ ĠIn Ġthe Ġimmediate Ġpost Ġ@ - @ Ġwar Ġperiod ĠAustralia Ġcontributed Ġsignificant Ġforces Ġto Ġthe ĠAllied Ġoccupation Ġof ĠJapan Ġas Ġpart Ġof Ġthe ĠBritish ĠCommonwealth ĠOccup ation ĠForce Ġ( ĠB CO F Ġ) Ġ, Ġwhich Ġincluded Ġforces Ġfrom ĠAustralia Ġ, ĠBritain Ġ, ĠIndia Ġand ĠNew ĠZealand Ġ. ĠAt Ġits Ġheight Ġin Ġ1946 Ġthe ĠAustralian Ġcomponent Ġconsisted Ġof Ġan Ġinfantry Ġbrigade Ġ, Ġfour Ġwarships Ġand Ġthree Ġfighter Ġsquad rons Ġ, Ġtot alling Ġ13 Ġ@ , @ Ġ500 Ġpersonnel Ġ. ĠThe ĠAustralian ĠArmy Ġcomponent Ġinitially Ġconsisted Ġof Ġthe Ġ34 th ĠBrigade Ġwhich Ġarrived Ġin ĠJapan Ġin ĠFebruary Ġ1946 Ġand Ġwas Ġbased Ġin ĠHiroshima ĠPre fecture Ġ. ĠThe Ġthree Ġinfantry Ġbatt alions Ġraised Ġfor Ġoccupation Ġduties Ġwere Ġdesignated Ġthe Ġ1 st Ġ, Ġ2 nd Ġand Ġ3 rd Ġbatt alions Ġof Ġthe ĠRoyal ĠAustralian ĠRegiment Ġin Ġ1949 Ġ, Ġand Ġthe Ġ34 th ĠBrigade Ġbecame Ġthe Ġ1 st ĠBrigade Ġwhen Ġit Ġreturned Ġto ĠAustralia Ġin ĠDecember Ġ1948 Ġ, Ġforming Ġthe Ġbasis Ġof Ġthe Ġpost Ġ@ - @ Ġwar ĠRegular ĠArmy Ġ. ĠFrom Ġthat Ġtime Ġthe ĠAustralian ĠArmy Ġcontribution Ġto Ġthe Ġoccupation Ġof ĠJapan Ġwas Ġreduced Ġto Ġa Ġsingle Ġunder Ġ@ - @ Ġstrength Ġbattalion Ġ. ĠAustralian Ġforces Ġremained Ġuntil ĠSeptember Ġ1951 Ġwhen Ġthe ĠB CO F Ġceased Ġoperations Ġ, Ġalthough Ġby Ġthe Ġtime Ġthe Ġmajority Ġof Ġunits Ġhad Ġbeen Ġcommitted Ġto Ġthe Ġfighting Ġon Ġthe ĠKorean Ġpen ins ular Ġfollowing Ġthe Ġoutbreak Ġof Ġthe ĠKorean ĠWar Ġin Ġ1950 Ġ. ĠThe ĠR AAF Ġcomponent Ġconsisted Ġof ĠNos . Ġ76 Ġ, Ġ77 Ġand Ġ82 ĠSquad rons Ġas Ġpart Ġof ĠNo . Ġ81 ĠWing ĠR AAF Ġflying ĠP Ġ@ - @ Ġ51 ĠMust angs Ġ, Ġinitially Ġbased Ġat ĠB of u Ġfrom ĠMarch Ġ1946 Ġ, Ġbefore Ġtransferring Ġto ĠIw ak uni Ġin Ġ1948 Ġ. ĠHowever Ġ, Ġby Ġ1950 Ġonly ĠNo . Ġ77 ĠSquadron Ġremained Ġin ĠJapan Ġ. ĠA Ġtotal Ġof Ġten ĠR AN Ġwarships Ġserved Ġin ĠJapan Ġduring Ġthis Ġperiod Ġ, Ġincluding ĠH MA ĠShips ĠAustralia Ġ, ĠHob art Ġ, ĠSh ro ps hire Ġ, ĠAr unta Ġ, ĠB ata an Ġ, ĠCul go a Ġ, ĠM urch ison Ġ, ĠSho al haven Ġ, ĠQuad rant Ġand ĠQu iber on Ġ, Ġwhile ĠHM AS ĠShips ĠMan oor a Ġ, ĠWest ral ia Ġand ĠK anim bl a Ġalso Ġprovided Ġsupport Ġ. Ġ Ġ Ġ= Ġ= ĠCold ĠWar Ġ= Ġ= Ġ Ġ Ġ= Ġ= Ġ= ĠEarly Ġplanning Ġand Ġcommitments Ġ= Ġ= Ġ= Ġ Ġ ĠDuring Ġthe Ġearly Ġyears Ġof Ġthe ĠCold ĠWar Ġ, ĠAustralian Ġdefence Ġplanning Ġassumed Ġthat Ġin Ġthe Ġevent Ġof Ġthe Ġoutbreak Ġof Ġa Ġglobal Ġwar Ġbetween Ġthe ĠWestern Ġworld Ġand ĠEastern Ġbloc Ġcountries Ġit Ġwould Ġneed Ġto Ġcontribute Ġforces Ġunder Ġcollective Ġsecurity Ġarrangements Ġas Ġpart Ġof Ġthe ĠUnited ĠNations Ġ, Ġor Ġa Ġcoalition Ġled Ġby Ġeither Ġthe ĠUnited ĠStates Ġor ĠBritain Ġ. ĠThe ĠMiddle ĠEast Ġwas Ġconsidered Ġthe Ġmost Ġlikely Ġarea Ġof Ġoperations Ġfor ĠAustralian Ġforces Ġ, Ġwhere Ġthey Ġwould Ġmost Ġlikely Ġoperate Ġwith ĠBritish Ġforces Ġ. ĠEarly Ġcommitments Ġincluded Ġthe Ġinvolvement Ġof ĠR AAF Ġair crew Ġduring Ġthe ĠBerlin ĠAirl ift Ġin Ġ1948 ĠâĢĵ Ġ49 Ġand Ġthe Ġdeployment Ġof ĠNo . Ġ78 ĠWing ĠR AAF Ġto ĠMalta Ġin Ġthe ĠMediterranean Ġfrom Ġ1952 Ġto Ġ1954 Ġ. ĠMeanwhile Ġ, Ġdefence Ġprepared ness Ġinitiatives Ġincluded Ġthe Ġintroduction Ġof Ġa ĠNational ĠService ĠScheme Ġin Ġ1951 Ġto Ġprovide Ġmanpower Ġfor Ġthe Ġcitizen Ġforces Ġof Ġthe ĠArmy Ġ, ĠR AAF Ġand ĠR AN Ġ. Ġ Ġ Ġ= Ġ= Ġ= ĠKorean ĠWar Ġ, Ġ1950 ĠâĢĵ Ġ53 Ġ= Ġ= Ġ= Ġ Ġ ĠOn Ġ25 ĠJune Ġ1950 Ġ, Ġthe ĠNorth ĠKorean ĠArmy Ġ( ĠK PA Ġ) Ġcrossed Ġthe Ġborder Ġinto ĠSouth ĠKorea Ġand Ġadvanced Ġfor Ġthe Ġcapital ĠSeoul Ġ, Ġwhich Ġfell Ġin Ġless Ġthan Ġa Ġweek Ġ. ĠNorth ĠKorean Ġforces Ġcontinued Ġtoward Ġthe Ġport Ġof ĠP us an Ġand Ġtwo Ġdays Ġlater Ġthe ĠUnited ĠStates Ġoffered Ġits Ġassistance Ġto ĠSouth ĠKorea Ġ. ĠIn Ġresponse Ġthe ĠUnited ĠNations ĠSecurity ĠCouncil Ġrequested Ġmembers Ġto Ġassist Ġin Ġrepe lling Ġthe ĠNorth ĠKorean Ġattack Ġ. ĠAustralia Ġinitially Ġcontributed ĠP Ġ@ - @ Ġ51 ĠMustang Ġfighter Ġ@ - @ Ġbomber Ġaircraft Ġfrom ĠNo . Ġ77 ĠSquadron ĠR AAF Ġand Ġinfantry Ġfrom Ġthe Ġ3 rd ĠBattalion Ġ, ĠRoyal ĠAustralian ĠRegiment Ġ( Ġ3 ĠR AR Ġ) Ġ, Ġboth Ġof Ġwhich Ġwere Ġstationed Ġin ĠJapan Ġas Ġpart Ġof Ġthe ĠB CO F Ġ. ĠIn Ġaddition Ġ, Ġit Ġprovided Ġthe Ġmajority Ġof Ġsupply Ġand Ġsupport Ġpersonnel Ġto Ġthe ĠBritish ĠCommonwealth ĠForces ĠKorea Ġ. ĠThe ĠR AN Ġfr igate ĠHM AS ĠSho al haven Ġ, Ġand Ġthe Ġdestroyer ĠHM AS ĠB ata an Ġ, Ġwere Ġalso Ġcommitted Ġ. ĠLater Ġ, Ġan Ġaircraft Ġcarrier Ġstrike Ġgroup Ġaboard ĠHM AS ĠSydney Ġwas Ġadded Ġto Ġthe Ġforce Ġ. Ġ Ġ ĠBy Ġthe Ġtime Ġ3 ĠR AR Ġarrived Ġin ĠP us an Ġon Ġ28 ĠSeptember Ġ, Ġthe ĠNorth ĠKoreans Ġwere Ġin Ġretreat Ġfollowing Ġthe ĠIn ch on Ġland ings Ġ. ĠAs Ġa Ġpart Ġof Ġthe Ġinvasion Ġforce Ġunder Ġthe ĠUN ĠSupreme ĠCommander Ġ, ĠGeneral ĠDouglas ĠMacArthur Ġ, Ġthe Ġbattalion Ġmoved Ġnorth Ġand Ġwas Ġinvolved Ġin Ġits Ġfirst Ġmajor Ġaction Ġat ĠBattle Ġof ĠYong ju Ġnear ĠPyongyang Ġon Ġ22 ĠOctober Ġ, Ġbefore Ġadvancing Ġtowards Ġthe ĠY al u ĠRiver Ġ. ĠFurther Ġsuccessful Ġactions Ġfollowed Ġat ĠKu jin