From Indian Summer: The Secret History of the End of an Emperor, by Alex von Tunzelmann (Picador, 2008), pp. 127-128:
IN JUNE 1942, [American journalist] Louis Fischer spent a week at Gandhi’s ashram and observed the preparations for a new campaign under the slogan “Quit India.” The slogan was not only catchy but accurate: the British administration was to be harried, disobeyed and besieged until it simply upped and left, war or no war, economy or no economy, responsibility or no responsibility. The Quit India resolution, passed by Congress on 8 August 1942, announced that Congress would “no longer [be] justified in holding the nation back from endeavouring to assert its will” against the British administration, and sanctioned “a mass struggle on nonviolent lines under the inevitable leadership of Gandhiji.” The struggle would only begin at Gandhi’s word; but this was a call for treason as far as the British were concerned. The first arrests were made in the early hours of the morning of 9 August.
Over the following days, India exploded in violent uprisings, described by the viceroy, Lord Linlithgow, as the “most serious since that of 1857.” There were Quit India hartals across the country, which turned into riots. The police and the army fought back, often brutally, leaving an official civilian death toll of 1,028; bazaar gossip put the total at 25,000. Effectively, Congress had given the raj an excuse to imprison hundreds of its leaders, including Gandhi himself and Nehru—who, according to his sister, was almost thankful for it, so uncomfortable had he felt opposing the war effort. The resolution could never have succeeded. Britain could not evacuate India in the middle of the Second World War, with Japan looming on its eastern front. But the empty space created in politics by the Congress leaders being in prison gave the Muslim League its chance to rush in.
According to Jinnah, it was not in the interest of the Muslims for the British to abandon them in a potentially hostile swamp of Hinduism. The logical position of the League was actually to keep the British in India—at least for as long as it took to convince them of the case for Pakistan, and perhaps indefinitely. The effect of Gandhi’s Quit India misstep, and the League’s hugely successful campaign during the 1940s, can be seen from the election statistics. In the general election of 1945–46, the Muslim League would win about 75 percent of all Muslim votes. In every previous election, its share of the Muslim vote had hovered around 4.6 percent. During the war years, Gandhi and Congress handed Jinnah a sixteenfold increase in his support. Quit India damaged the chances of a united India at least as much as any single act of the British administration ever had.
Linlithgow wrote to Churchill, admitting that he was concealing the severity and the extent of the violence from the world. But the Americans found out and sent their own mediators to Delhi. The Americans’ “zeal in teaching us our business is in inverse ratio to their understanding of even the most elementary of problems,” Linlithgow complained to the secretary of state for India, Leopold Amery. It would be bad if the Americans came, he averred; it would be worse still if they tried to talk to Gandhi or Nehru. He pleaded with Amery “to arrest at least for a time this flow of well meaning sentimentalists.” But the flow of Americans continued, and Indians delighted to see them spoiling official occasions for the British by wearing the wrong clothes, disregarding procedure and cheerfully ignoring distinctions of rank.