An Alternate History Story

Idea
The Idea of An Alternate History Story, is similar to a book, we will ad a theme, and you might write a story about it, with characters, and all, similar to the plot of a movie described in wikipedia. More than one story of the same theme is allowed but it must be plausible!

American-Soviet World War III

 * 1949Castle-bravo-atomic-nuclear-bomb-test.jpg
 * 1956
 * 1962
 * 1983
 * 1991