Japanese are skeptical of an invasion of India doubting their logistics. Though the Aung San Government of Burma is helping with whatever it has got, the jungles approaching India are harsh and if the lines are cut by the British, it is going to be very hard to establish the logical lines. The motives for an invasion are not geo-strategic but political and personal. Only two persons in Burma area with any level of standing pitch for an invasion of India. One is Lt Gen Renya Mutaguchi, who was never a front line general and wants some personal glory. The other is Subhas Chandra Bose who was in Burma only for invasion of India.
Renya Mutaguchi argues for an invasion citing three reasons -
1. More provisions and better logistics if Assam is taken. The huge armies cannot live of Burmese lands for a long time. The forecast is that a famine is expected in the next two years.
2. The most remote and solid supply lines the Chinese have is Ledo Road. If the road is taken, the link between India and China will be broken.
3. This attack will give a chance for Invasion of China through North Burma. Since all the invasions starting from Indochina to Burma are to open multiple fronts against China to crush it and free up the armies tied in invasion, an attack can be coordinated with the Indochina Armies and Manchurian Armies to end the China War.
Operation Ha Go is aimed to soften the Imphal defenses by diverting the forces to Chittagong theatre. Ha Go is not aimed to be a success but is expected to hold up British forces for a sufficient time.
Indian National Army's soldiers, who are mainly from that area tell that invasion of Imphal is impossible due to the terrain. The plan will still be the original and once the forces are tied up in Imphal, 28th Army will launch a surprise attack supporting Ha Go. Shōzō Sakurai, the head of 28th Army is contacted and he assents to the plan. To maximize British defections, INA forces are told to fight only Indian forces and none else. The Port Blair and Rangoon fleets are ordered not to shell Indian mainland for political implications.
Operation Ha Go is launched with 55th division with the target Ngakyedauk on 5 Feb 1944. Intelligence comes that the complete 15th Army is marching towards Imphal-Kohima Axis the next day. British first try to drive a wedge a gap between both the forces and trap the 15th Army completely. Seeing their logistics position and troop morality, they decide to hold on to Imphal but with a sufficient force to tie up 55th Division.
23 Feb 1944 15th Army is completely tied up in Imphal and Kohima. Whenever British forces attack, INA launches the defence. If it is an Indian force, it fights tenaciously while if it is a British force, they retreat back to let the Japanese fight. INA forces swell to 57000 from a paltry 8000 forces.
25 Feb 1944 28th Army advances suddenly towards Ngakyedauk.
26 Feb 1944 Kohima forces withdraw in the night and march on Dimapur to take the British from the back.
28 Feb 1944 Ngakyedauk falls
3 Mar 1944 Cox Bazar falls. Chittagong is bypassed and forces turn towards Agartala. INA forces move towards Dhaka to incite a rebellion.
4 Mar 1944 Agartala falls.
5 Mar 1944 Dimapur falls.
6 Mar 1944 Tezpur and Saraighat Bridges destroyed. British supply lines are non-existent both by road and rail.
8 Mar 1944 28th Army and 15th Army combine forces at Sylhet. 75,000 soldiers of INA, now numbering 87,000 march towards Dhaka to take Bengal. The rest are assigned to Imphal theatre. The march to Dhaka creates a general insurrection and all Bengal until Murshidabad
11 Mar 1944 Air attacks on Kohima 80% of British planes and 50% of Japanese planes in India and Burma theatre are destroyed.
11 Mar 1944 Battles of Nadia and Nawabganj between British forces from Ranchi Command and INA forces. Bose orders the soldiers to shed uniforms and fight as civilians. The British Indian forces are ready to fight an enemy army and not Indian civilians. The soldiers rebel and Ranchi is taken by 13 March. The road to Delhi is open and Delhi falls on 17 March.
12 Mar 1944 Secret communications established with the king of Manipur who agrees to surrender the city.
14 Mar 1944 Rebellion in Imphal. William Slim is assassinated and 5000 British soldiers are killed. Indian soldiers surrender en masse.
15 Mar 1944 Imphal taken. 67,000 British soldiers and 34,000 British Indian forces taken prisoner. Of the Indian forces, 13,000 join INA and the rest are dispersed.
19 March 1944 India declares independence. All British are interned in India. For the time being, the kingdoms are left as it is.
22 March 1944 India orders its soldiers to surrender to the Japanese and German forces all over the world. British forces in Europe are suddenly cut short by half. Seeing Indians crossing the lines, 30% of colonial forces in Europe rebel. They are granted Indian citizenship and are asked to fight for the Axis. British forces suddenly fall from 670,000 soldiers to 240,000 soldiers in Europe. Indian soldiers in England awaiting Normandy landings rebel.With the rebellion, the secret of troop concentration is out and the naval force to support Normandy landings is destroyed. The course of war is a different spin off altogether.
25 April 1944 Japan collects its forces, gets new armour and planes and launches an attack into China in co-ordination with the other field armies.
8-31 Aug 1944 Battle of Chengdu Mao Zedong killed and Zhou En Lai captured seriously injured. Communist leadership is in disarray and surrender en masse to the KMT.
27 Oct-14 Dec 1944 Battle of Wuhan. Chinese field army of KMT surrenders. Chiang Kai-Shek escapes to Australia.
31 Dec 1944 China surrenders and Chinese army is asked to invade Siberia. Reconstruction of China starts.
What happens now? Will the Russian juggernaut stop? Will Russia be dismembered permanently, with Siberia permanently partitioned between Japan, Manchukuo, China and Mengjiang? Will Japan send forth feelers of peace to America? Will the atomic bombs still happen? With both Russia and Britain breaking, will USA become a hermit kingdom? Will it still prefer to crush Germany while negotiating peace with Japan?