Martin, George R.R. "Under Siege"
Divergence: 1856 CE
What if: John C. Fremont was elected US president in 1856.
Summary: A mental time traveler trying to prevent the Russian capture of Sveaborg in 1808 fails, but later emigrates to America and becomes a Republican.
Published: In Omni, October 1985; The Year's Best Science Fiction, Third Annual Collection (ed. Gardner Dozois), Bluejay 1986 (031294487X, 0312944861); Portraits of His Children, Dark Harvest 1987 (0913165182, 0913165190), Baen 1992 (0671721240BUY); and Futures Past (eds. Jack Dann and Gardner Dozois), q.v.
Original in: English.
Translation: German by Barbara Heidkamp as "Belagert", in Hiroshima soll leben! Die schönsten Alternativwelt-Geschichten (ed. Karl Michael Armer), q.v.