The Edge of the Knife by H. Beam Piper. The Terro-Human Future History is Piper's detailed account of the next 6000 years of human history. 1942, the year the first fission reactor was constructed, is defined as the year 1 A.E. (Atomic Era). In 1973, a nuclear war devastates the planet, eventually laying the groundwork for the emergence of a Terran Federation, once humanity goes into space and develops antigravity technology.
The story 'The Edge of the Knife' (collected in Empire) occurs slightly before the war, and involves a man who sees flashes of the future. It links many key elements of Piper's series.
The Edge of the Knife by H. Beam Piper. Free audio book summary by Wikipedia and reading by Jfmarchini.
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