Excerpts from Books and Wikipedia
"Many Americans meanwhile interpreted Khrushchev's quote as a nuclear threat." [Wikipedia]
"In the first fifteen years after the Second World War the economies of the 'socialist camp' grew considerably faster than those of the West, so much so that Soviet leaders like Nikita Khrushchev sincerely believed that, the curve of their growth continuing upwards at the same rate, socialism would out produce capitalism within a foreseeable future;" [Hobsbawm: Extremes, p. 377]
"The third drawback of the system, and the one which in the end sank it, was its inflexibility. It was geared to constant growth in the output of products whose character and quality had been predetermined, but it contained no built-in mechanism for varying either quantity (except upward) or quality, or for innovation." [Hobsbawm: Extremes, p. 384]