on as the Prime Minister of the United States of Indonesia and presided over the transition of the federal state to the unitary state, which was made official on 17 August 1950. Vice Presidency (1945–1956) Intellectual pursuits and cooperatives Indonesia soon adopted a constitution which advocated parliamentary democracy and reduced the president to the role of a ceremonial head of state. That left Hatta with little to do as vice president, especially since his term as prime minister was not renewed. For his remaining time as vice president, Hatta was regularly invited to deliver lectures in universities. He also engaged in intellectual pursuits, writing essays and books about topics such as the economy and cooperatives. The idea of cooperatives being an integral part of economy would become a pet project for Hatta and he would become an enthusiastic promoter of the idea. In July 1951, on the occasion of Cooperatives Day, Hatta went on the radio to deliver a speech on cooperatives. In 1953, Hatta's contribution towards promoting cooperatives was recognized and he was given the title "Father of Indonesian Cooperatives" at the Indonesian Cooperative Congress. Setting Indonesia's foreign policy doctrine Aside from cooperatives, Hatta's other main contribution to Indonesia governance was the setting of the nation's foreign policy doctrine. In 1948, Hatta delivered a speech called "Rowing Between Two Rocks". In it, he referred to the Cold War and the conflict between the United States and the Soviet Union. Hatta said that Indonesian foreign policy has to look after its own interest first, not that of the US and the USSR. In saying this, Hatta wanted Indonesia to be independent in deciding its stance during the Cold War. Hatta also added that Indonesia should be an active participant in world politics so that once again it would be Indonesia's interests that came first. This doctrine, which would become known as the "Independent and Active" doctrine, continues to be the basis of Indonesian foreign policy. Retirement Announcement and cause In 1955, Hatta announced that when the new People's Representative Council (DPR) as well as the Constitutional Assembly, a body commissioned to create a new constitution, were formed as a result of the year's legislative and assembly elections, he would retire from the vice presidency. He announced this intention in a letter to Sukarno. On the surface, it seemed as if Hatta was retiring for practical reasons. Because the presidency was