Guns of the North

An alternate of an alternate, from Turtledove's Timeline-191. Enjoy!

A map of North America, as seen in Eric G. Iverson's "Guns of the North". When American time travellers from the year 2017 arrive in the camp of General George B. McClellan in 1862. With knowledge of the Confederate victory at Antietam, the time travellers give McClellan a collection of history books, as well as an armoury of M1 Thompson submachine guns and ammunition. This leads the Union to victory over the Confederacy at Antietam, and the capture of Robert E. Lee. In 1863, McClellan leads the Union forces on a march that captures Richmond, ending the Southern Rebellion.

After Abraham Lincoln's second term ends, McClellan runs for and wins the Presidency on a "National Union Party" ticket. The NUP becomes a dominant force in American politics, replacing the obsolete Democratic Party in the 1870s. The United States goes to war with the Mexican Empire, annexing the border states and putting a republican government in power. McClellan declines to run for a third term.

The last chapters of Iverson's book show a victorious and technologically-advanced United States that has, with its American allies, kicked the French Empire out of the Western Hemisphere. The US and its bloc are in a "non-violent conflict" with the increasingly-authoritarian British Empire. The Canadian border is a heavily-guarded zone, with mines and bunkers all along the 49th parallel.