Question: What campaign was launched by "Bomber" Harris?

Context paragraphs:
Longhai Campaign: Longhai Campaign (陇海战役), also known as the Campaign along the Longhai (Lanzhou – Lianyungang) Railway (陇海路战役), was a campaign launched against the nationalists by the communists during Chinese Civil War in the post World War II era.  The campaign was a coordinated offensive in support of the other two campaigns the Communists launched against the nationalists, namely, the Campaign of the North China Plain Pocket and the Central Jiangsu Campaign.  Longhai Campaign resulted in the communist victory, achieving the Communists objective of relieving the pressure on their comrades in the other two campaigns this one supported, enabling those in the Campaign of the North China Plain Pocket successfully escape from the nationalists and those in the Central Jiangsu Campaign to also score a huge victory over the nationalists.

No. 6 Squadron RAAF: No. 6 Squadron is a Royal Australian Air Force (RAAF) training and bomber squadron.  It was formed in 1917 and served as a training unit based in England during World War I.  The squadron was disbanded in 1919 but re-formed at the start of 1939.  It subsequently saw combat as a light bomber and maritime patrol squadron during World War II, and took part in the New Guinea Campaign and New Britain Campaign before being disbanded after the war.

Colin &quot;Bomber&quot; Harris vs Colin &quot;Bomber&quot; Harris: Colin &quot;Bomber&quot; Harris vs Colin &quot;Bomber&quot; Harris

Big Week: From February 20–25, 1944, as part of the European strategic bombing campaign, the United States Strategic Air Forces (USSTAF) launched Operation Argument, a series of missions against Nazi Germany that became known as Big Week.  The planners intended to lure the Luftwaffe into a decisive battle by launching massive attacks on the German aircraft industry.  By defeating the Luftwaffe, the Allies would achieve air superiority and the invasion of continental Europe could proceed.  The daylight bombing campaign was also supported by RAF Bomber Command, operating against the same targets at night.  Arthur Harris resisted contributing RAF forces as it diverted them from the British area bombing offensive.  It took a direct order from Air Chief Marshal Sir Charles Portal, Chief of the Air Staff, to force Harris to comply.  RAF Fighter Command also provided escort for USAAF bomber formations, just at the time that the Eighth Air Force had started introducing the P-51 long-range fighter to take over the role.  This major offensive overlapped the German Operation Steinbock, the "baby blitz" against the United Kingdom, which itself lasted from January through May 1944.

Sir Arthur Harris, 1st Baronet: Marshal of the Royal Air Force Sir Arthur Travers Harris, 1st Baronet, {'1': ", '2': ", '3': ", '4': "} (13 April 1892 – 5 April 1984), commonly known as "Bomber" Harris by the press and often within the RAF as "Butcher" Harris, was Air Officer Commanding-in-Chief (AOC-in-C) RAF Bomber Command during the height of the Anglo-American strategic bombing campaign against Nazi Germany in the Second World War.  In 1942, the British Cabinet agreed to the "area bombing" of German cities.  Harris was tasked with implementing Churchill's policy and supported the development of tactics and technology to perform the task more effectively.  Harris assisted British Chief of the Air Staff Marshal of the Royal Air Force Charles Portal in carrying out the United Kingdom's most devastating attacks against the German infrastructure and population, including the Bombing of Dresden.

RCAF Western Air Command: Western Air Command was the part of the Royal Canadian Air Force's Home War Establishment responsible for air operations on the Pacific coast of Canada during the Second World War.  When Canada declared war against Germany in September 1939 the command consisted of only five squadrons.  Four of them equipped with obsolete aircraft including a bomber squadron with aircraft from the Great War and there were no fighter aircraft at all for its only fighter squadron (113 Fighter Squadron was thus disbanded).  With the Japanese threat after Pearl Harbor it grew rapidly and played a critical role in fighter and anti-submarine operations in Canadian and American waters during the Aleutian Islands Campaign.  It was there that Squadron Leader K.A. Boomer of No. 111 Squadron shot down a Rufe fighter, the RCAF's only kill in the Pacific Theatre.  On 7 July 1942 a Bristol Bolingbroke pressed home an attack on the Japanese Submarine Ro 32 the pilot F/Sgt.  P.M.G. Thomas of No. 115 Squadron RCAF then led American Destroyers to sink the damaged submarine.  By January 1943 Western Air Command had expanded to include many bomber, fighter and operational units under its control.  By the end of the war the command would involve some twenty squadrons when the last units to join were added in 1943.  These were the 163 Army Cooperation Squadron in March flying Bristol Bolingbrokes and Hawker Hurricanes, in May the 160 Bomber-Reconnaissance Squadron was added flying Cansos from Sea Island BC (before moving to Yarmouth NS in July) and the 166 Communication Squadron formed in September flying various types.  In addition to the new squadrons, new aircraft types came on line replacing the command's remaining Supermarine Stranraers and Blackburn Sharks with Canso's and the Bolingbrokes and Beauforts with the Lockheed Ventura.  Countless training missions and operational patrols bolstered the air activity over the coastal areas but there was not much action until RCAF Western Command was on the look out for General Kusaba's Fire Balloons that the Japanese called the Fūsen Bakudan Campaign.  In February and March 1945, P-40 fighter pilots from 133 Squadron, Royal Canadian Air Force operating out of RCAF Patricia Bay (Victoria, British Columbia), intercepted and destroyed two fire balloons, On 21 February, Pilot Officer E. E. Maxwell While shot down a balloon, which landed on Sumas Mountain, in Washington State.  On 10 March, Pilot Officer J. O. Patten destroyed a balloon near Saltspring Island, British Columbia.  During another interception a Canso forced down a fire balloon which was examined at the army headquarters.  Patrol activity was joined by the Operational Training Schools (OTS) operated by Number 4 Training Command of the BCATP.  They were the No. 3 OTS flying the Canso and Catalina and No. 32 OTS with Ansons, Beauforts and Swordfish at Patricia Bay.  In April, 1944 the No. 5 OTS Heavy Conversion unit stood up at Boundary Bay when 16 B-24 Liberators arrived fresh from American factories.  By the end of September 1944 RCAF 5 O.T.U. had grown to sizeable force of some 87 aircraft including 38 B-24 Liberators, 35 B-25 Mitchells, 5 Bolingbrokes, 8 P-40 Kittyhawks and a single Norseman.  With the end of the war in Europe these aircraft were joined by a number of Victory Aircraft Lancaster X bombers which were to be used to train the British Commonwealth's Very Long Range Bomber Tiger Force that would soon be sent to bomb the Japanese mainland from Okinawa.  With the unconditional surrender of Japan the RCAF's Tiger Force bomber squadrons were disbanded before they flew overseas and the total draw down of the Western Air Command was suddenly undertaken.  Within several months almost all the flying squadrons would be completely stood down.

Battle of Berlin (RAF campaign): The Battle of Berlin was the British bombing campaign on Berlin from November 1943 to March 1944.  Not limited solely to Berlin, the campaign targeted other German cities as well, to prevent the concentration of defences in Berlin.  The campaign was launched by Air Chief Marshal Sir Arthur Harris, AOC of RAF Bomber Command in November 1943.  Harris believed this could be the blow that broke German resistance: "We can wreck Berlin from end to end if the USAAF come in with us.  It will cost us between 400 and 500 aircraft.  It will cost Germany the war".  By this time he could deploy over 800 long-range bombers on any given night, equipped with new and more sophisticated navigational devices such as H2S radar.  Between November 1943 and March 1944, Bomber Command made 16 massed attacks on Berlin.  The USAAF, having recently suffered heavy losses in its attacks on Schweinfurt from which it was still recovering, was unable to participate.

Operation Linebacker II: Operation "Linebacker II" was a US Seventh Air Force and US Navy Task Force 77 aerial bombing campaign, conducted against targets in the Democratic Republic of Vietnam (North Vietnam) during the final period of US involvement in the Vietnam War.  The operation was conducted from 18 to 29 December 1972, leading to several informal names such as "The December Raids" and "The Christmas Bombings".  Unlike the Operation Rolling Thunder and Operation Linebacker interdiction operations, "Linebacker II" was to be a "maximum effort" bombing campaign to "destroy major target complexes in the Hanoi and Haiphong areas, which could only be accomplished by B-52s".  It saw the largest heavy bomber strikes launched by the US Air Force since the end of World War II.  "Linebacker II" was a modified extension of the Operation Linebacker bombings conducted from May to October, when the emphasis of the new campaign shifted to attacks by B-52s rather than smaller tactical fighter aircraft.

4th Air Group: The 4th Air Group (第四航空隊 , Dai Yon Kōkūtai ) was a land-based bomber aircraft unit of the Imperial Japanese Navy Air Service (IJNAS) during the Pacific campaign of World War II.  The unit was formed on 10 February 1942 and flew the Mitsubishi G4M "Rikko" Navy Type 1 Attack Bomber aircraft.  That same month, the 4th Naval Air Group (NAG) deployed to Rabaul, New Britain and supported Japanese operations during the early stages of the New Guinea Campaign, first as part of the 24th Air Flotilla and from April as part of the 25th Air Flotilla.  The newly arrived unit took heavy losses on 20 February during an action off Bougainville, losing 15 of 17 bombers sent to attack a United States Navy aircraft carrier task force.

No. 21 Squadron RAAF: No. 21 Squadron is a Royal Australian Air Force (RAAF) general reserve squadron.  Formed in the mid-1930s as a unit of the part-time Citizen Air Force (CAF), it was mobilised for service during World War II, when it saw action against the Japanese as a fighter unit in the Malayan campaign, a dive bomber unit in the New Guinea campaign, and a heavy bomber unit in the Borneo campaign.  After the war, the squadron continued to fly until 1960, when the CAF ceased flying operations.  At that time, No. 21 Squadron converted to a non-flying support role, which it currently fulfils at RAAF Williams.

Supporting paragraphs: Battle of Berlin (RAF campaign) Sir Arthur Harris, 1st Baronet
Answer: Battle of Berlin