Ultimatum

An early example of ambitious science fiction in which atomic physics and aeronautic technology are used to bring about world peace and remove the immanent threat of global warfare (<a href= Amusingly, although set mainly in the USA, measurements are given in the metric system, which a footnote in Chapter III states was adopted in the USA in 1929. Curiously, I believe the USA was the second nation after France to officially adopt the metric system, but the adoption was, of course, ineffectual.