Great Britain wasted a huge opportunity in India before WW I and II, that would have boosted the empire considerably. In 1939 India produced 1 million tons of steel, versus 1.2 million tons of Australia, although the population of India was 389 million and that of Australia 7 million and India had very inexpensive labor and huge reserves of iron ore. Britian didn't use the inexpensive labor to manufacture ships, tanks, etc, in large scale. The Indian navy had few and obsolete ships, weaker than the Australian navy. Although millions of Indians served in WW II, they were few pilots and no generals among them. Agricultural production was also very low in most of India, which had to rely on rice from Burma and southern India. GB saw India more like a place to dump its products and to get inexpensive opium, tea, indigo, etc, and a source of cannon fodder than a powerhouse and an invaluable asset it had to develop and defend at any cost.
In 1941, while Japan was preparing to invade most of the far east, Churchill sent over 500 hurricanes and a lot more equipment to Stalin, whom he had denounced publicly for decades as the worst tyrant. These planes, etc, were desperately needed in the far east. GB bought a few very inferior Brewster Buffaloes and sent them to Singapore, etc, Had all the planes that were sent to the Soviets been in Malaya-Singapore, Rangoon, Ceylon, etc, with the Buffaloes, The Japanese may have thought twice about attacking British territories and would have lost more planes if they attacked. The Prince of Wales and Repulse would have at least stood a chance to survive the attack by Japanese bombers from Indochina and support the British forces in Malaya-Singapore with their powerful artillery. There were no tanks at all in Malaya and little field artillery, Churchill had sent a lot of troops with light armament, hoping that they could somehow resist.
Churchill was shocked when these ships were lost and enraged when Singapore capitulated so soon (losing about 100,000 troops, mostly Indian, about 30,000 of which joined the Japanese). He seemed to have forgotten that it was his decision to send the planes to Stalin and that without planes the ships were doomed and without ships, tanks and planes the troops did not stand a chance against the Japanese army with tanks and the support of hundreds of planes and the artillery of dozens of ships.
Rangoon fell for the same reasons, blocking the flow of supplies to China and depriving India of rice (Burma was the largest rice exporter in the world) and providing rice and oil for the Japanese. For almost a year the Chinese army had to fight the Japanese without supplies.
It is ironic that the British would transport hundreds of thousands of Indian troops to the Mediterranean and would not supply enough airplanes to defend Rangoon, so that millions of Indians would starve to death. Although Roosevelt tasked Churchill with recapturing Burma so the Chinese could be supplied, Britian did very little in Burma for years, so the Americans had to waste enormous amounts of fuel, planes, aviators, etc, to fly supplies to China over the Himalayas.
