Why did the cabinet missions failed in 1946?
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 Early in 1946, the Labour Government dispatched an all-party parliamentary delegation to India to meet Indian leaders and convince them of the British desire for an early settlement of the Indian constitutional issue. However, it was only in March 1946 that with the arrival of three Cabinet Ministers, Lord Pethick-Lawrence, Sir Stafford Cripps and Mr. A. V. Alexander, a crucial stage was reached in the negotiations between the British Government and the Indian political parties. The negotiations were conducted on behalf of the Congress by Abul Kalam Azad who was assisted by Nehru and Patel. Gandhi was, however, frequently consulted. The negotiations were bogged down on the basic question whether India was to remain united or to be split up to satisfy the Muslim League's demand for Pakistan. The Congress opposed to the partition of the country, but was prepared to go to the farthest limit in conceding cultural, economic and regional autonomy to various regions. A conference at Simla failed to resolve the Congress-League differences. The Cabinet Mission then offered a compromise plan in their statement of May 16,1946. They sketched a three-tier constitutional structure for India. On the top was to be a Union of India embracing British India as well as the Indian States, but dealing only with foreign affairs, defence and communications. The bottom tier was to consist of Provinces and States in which were to vest all residuary powers. The intermediate tier was to comprise "groups" to be formed by Provinces (if they chose) to deal with certain common subjects. The Muslim League avowed its acceptance of the Cabinet Mission Plan, but this acceptance was more apparent than real, The League and its leaders made no secret of their hope and design that the new constitution would be used to effect a partition of the country. "Let me tell you," Jinnah told the Muslim League Council on June 5, 1946 "that Muslim India will not rest content until we have established full, complete and sovereign Pakistan." It was this apparent contradiction in the League's stand, which made Gandhi and his colleagues in the Congress uneasy about the "grouping of provinces", which the League wanted to make compulsory and a stepping-stone to Pakistan. The controversy on this issue wrecked the Cabinet Mission Plan.

Because he proposed that all the treaties should be made through the league of nations.