Like the entire 1961 test series in which it was conducted, the creation of the Tsar Bomba was the result of political calculation by the Soviet leadership, especially of Premier Nikita Khrushchev. A de facto moratorium had existed between the U.S., USSR and UK since the conclusion of the last U.S. and Soviet test series in 1958, and two years of discussion had been conducted regarding formal limitations on nuclear testing. But the Cold War continued at high pitch, with the occasional reductions in tension being only partial and transitory phenomena. Many high-stakes cards remained to be played by the Soviets - the erection of the Berlin Wall and the deployment of missiles to Cuba being notable examples. The decision to break the moratorium with a "testing spectacular" that coincided with the Twenty Second Congress of the Communist Party of the Soviet Union was a move cast in the same mold.
The Soviet weapons scientists had spent the three years since the last test series in 1958 developing new concepts and refining old ones, but they had not been preparing for a new test series per se until Khrushchev called a meeting with the "atomic scientists" - the leaders of the weapons program - on 10 July 1961. There was no discussion of whether more tests were necessary or desirable, which Sakharov, the senior weapon designer, very much doubted. Khrushchev simply began the meeting with a speech declaring that tests would resume in the fall to 'show the imperialists what we could do', a decision that came as a surprise to the scientists present. Khrushchev specifically cited as the primary motivation a political rather than a technical justification - his view that the international situation was deteriorating [Sakharov 1990, pg. 215]. From there on until the end of the test series it was an all-out effort to ready as many designs, concepts, and devices for testing as possible.
Available sources do not make it clear where the idea of the 100 megaton device test originated. Sakharov does not mention this device being proposed at the 10 July meeting, but first refers to it in connection with a mid-August review: "Khrushchev was already familiar with the test program, and in particular with our plan to explode a device of record-breaking power", implying that the idea of this test spectacular originated with the weapons team [Sakharov 1990, pg. 218]. Comments by Reed and Kramish [Reed and Kramish 1996] conversely indicate that the development and test of this device was a directive from Khrushchev at the July meeting. The detailed account by Adamsky and Smirnov [Adamsky and Smirnov 1998] do not address this at all. They do state that the development of the device began in the middle of July (i.e. immediately after the meeting) and that "We knew that the culmination of the series of tests planned in the USSR would be the explosion of the 50-Mt device, which was designed to produce explosions of up to 100 megatons" but do not indicate how they came to know this.
There was no previously existing military requirement for a 100 megaton weapon - such weapons are virtually useless for military purposes. The Soviet Union had only one delivery system capable of carrying a weapon of this size - a handful of the relatively slow prop-driven Tu-95 bomber - and it was incapable of intercontinental range with a payload this large. A 100 Mt weapon can level urban areas in a zone 60 km wide, cause heavy damage in a zone 100 km across, cause 3rd degree burns in a region 170 km across (only a bit smaller than the width of West Germany) and eye damage to 220 km. Such a weapon can only be used as a means of destroying an entire urban region - a major urban complex including suburbs and even neighboring cities. This scale of destruction is much larger than any discrete urban area in Western Europe. With its dense settlement, use of such a weapon in Europe is equivalent to an attack on a major portion of an entire nation and its population. Fallout from a low altitude or surface burst in central England could produce lethal exposures extending into the Warsaw Pact nations; a similar explosion in West Germany could create lethal fallout as far as the Soviet border. Even in the United States there were only three urban regions at that time large enough to conceivably merit attack with such a weapon - New York, Chicago, and Los Angeles. On any smaller target it would be simple overkill. Even if the Tu-95 were able to reach Chicago, the closest plausible U.S. target, (which is doubtful given the enormous payload, far in excess of normal for long-range missions, and the added drag from the belly bulge required to house the bomb) it would have been detected crossing the North American early warning line and then been over U.S. and Canadian territory for 8 hours - ample time for jet fighters to intercept and shoot it down [Zaloga 1993].
The Soviet weapons scientists had spent the three years since the last test series in 1958 developing new concepts and refining old ones, but they had not been preparing for a new test series per se until Khrushchev called a meeting with the "atomic scientists" - the leaders of the weapons program - on 10 July 1961. There was no discussion of whether more tests were necessary or desirable, which Sakharov, the senior weapon designer, very much doubted. Khrushchev simply began the meeting with a speech declaring that tests would resume in the fall to 'show the imperialists what we could do', a decision that came as a surprise to the scientists present. Khrushchev specifically cited as the primary motivation a political rather than a technical justification - his view that the international situation was deteriorating [Sakharov 1990, pg. 215]. From there on until the end of the test series it was an all-out effort to ready as many designs, concepts, and devices for testing as possible.
Available sources do not make it clear where the idea of the 100 megaton device test originated. Sakharov does not mention this device being proposed at the 10 July meeting, but first refers to it in connection with a mid-August review: "Khrushchev was already familiar with the test program, and in particular with our plan to explode a device of record-breaking power", implying that the idea of this test spectacular originated with the weapons team [Sakharov 1990, pg. 218]. Comments by Reed and Kramish [Reed and Kramish 1996] conversely indicate that the development and test of this device was a directive from Khrushchev at the July meeting. The detailed account by Adamsky and Smirnov [Adamsky and Smirnov 1998] do not address this at all. They do state that the development of the device began in the middle of July (i.e. immediately after the meeting) and that "We knew that the culmination of the series of tests planned in the USSR would be the explosion of the 50-Mt device, which was designed to produce explosions of up to 100 megatons" but do not indicate how they came to know this.
There was no previously existing military requirement for a 100 megaton weapon - such weapons are virtually useless for military purposes. The Soviet Union had only one delivery system capable of carrying a weapon of this size - a handful of the relatively slow prop-driven Tu-95 bomber - and it was incapable of intercontinental range with a payload this large. A 100 Mt weapon can level urban areas in a zone 60 km wide, cause heavy damage in a zone 100 km across, cause 3rd degree burns in a region 170 km across (only a bit smaller than the width of West Germany) and eye damage to 220 km. Such a weapon can only be used as a means of destroying an entire urban region - a major urban complex including suburbs and even neighboring cities. This scale of destruction is much larger than any discrete urban area in Western Europe. With its dense settlement, use of such a weapon in Europe is equivalent to an attack on a major portion of an entire nation and its population. Fallout from a low altitude or surface burst in central England could produce lethal exposures extending into the Warsaw Pact nations; a similar explosion in West Germany could create lethal fallout as far as the Soviet border. Even in the United States there were only three urban regions at that time large enough to conceivably merit attack with such a weapon - New York, Chicago, and Los Angeles. On any smaller target it would be simple overkill. Even if the Tu-95 were able to reach Chicago, the closest plausible U.S. target, (which is doubtful given the enormous payload, far in excess of normal for long-range missions, and the added drag from the belly bulge required to house the bomb) it would have been detected crossing the North American early warning line and then been over U.S. and Canadian territory for 8 hours - ample time for jet fighters to intercept and shoot it down [Zaloga 1993].
