The year is 1862, and the Union is losing the Civil War. Union attempts to capture Richmond have failed, and attempts by the Confederates to push the Union out of the south have failed. Nevertheless, Britain and France are moving closer to recognizing the Civil War, and feel the war has gone on long enough. Nevertheless, a new secret weapon is discovered by the US.
In 1942, a survived Bismarck, alongside the Scharnhorst, Admiral Scheer, Prinz Eugen, a few destroyers and a light cruiser carrying Panther, Tiger and Panzer IV tanks, as well as assault rifles, machine guns and bombs, are caught in an explosion and are sent to 1862.
The crews of the ships do not survive, but the vehicles and weapons do. A Union division under General Grant comes across the vehicles by chance. They investigate, and through trial and error, begin to utilize them. Grant realizes that if the Union utilized the ten tanks, two Tigers, four Panthers and four Panzer IVs, they could break the Confederate lines. They decide not to reveal them until a battle, when the Union cause seems lost.
This comes when the Confederates attack Antietam. Unlike in our timeline, three Union soldiers don't discover Lee's plan 191. This leaves the Union caught by surprise, and getting destroyed. Grant's arrival changes that. Union forces fronted by tanks, as well as machine and sub-machine guns, smash through the Confederate lines and cut them in two.
The tanks destroy everything in their path, and half the Army of Northern Virginia is captured. The remainder, just 10,000, escape. At the same time, Bismarck and Scharnhorst shell Charleston harbor, and Grant reveals to the President the Union's secret weapons.
Lincoln adopts the new weapons, and Union engineers begin reverse engineering the weapons. Alongside the decisive victory at Antietam, the new weapons cause Britain and France to completely stop support of the Confederacy, they don't want to face the Union army's tanks or the mighty battleships.
Union forces overrun Richmond and encircle the bulk of the Confederate armies when they cut a swathe through Virginia and Tennessee. Confederate forces surrender in droves, and a Union assault on the deep south fronted by thirty tanks, twenty of which are brand new. The Union seizes New Orleans and Charleston, and the heavy cruiser pair Admiral Scheer and Prinz Eugen hunt down Confederate surface raiders.
By December 1862, after less then two years of war, the Union celebrates a victory, and look in awe at the weapons that won them the war.
Congress votes overwhelmingly to operate these new weapons permanently. The Union also utilizes electricity and television and in a speech, Lincoln states that the victory was due to General Grant and God's resolve to stop slavery.
The Union scraps most of its ships, so as to gain money for building up its battleships, battle cruisers, heavy cruisers and destroyers. The Union researches and draws up proposals for more battleships. The Union government lowers its army to 50,000, though it does have 2,000 tanks by 1870.
Despite the fact that many countries will soon adopt the new technology, especially Britain, who is determined to stay on top of the world navally, as well as a strengthening Germany, the Union declares it will be ready for any future war. To prove it, four new battleships are ordered, the New York, Pennsylvania, Illinois, and California. There are also four more battle cruisers of the Scharnhorst-class; Indiana, Ohio, Missouri, and Nevada. Sub-machine guns and machine guns replace rifles and muskets as the main army armament. 500 Tigers, 1,000 Panzer IVs and 500 Panthers.
Following the end of the Civil War, the Union attempts to reverse engineer its naval and army weapons. Tanks, and machine guns have been reverse engineered, as has electricity and television, by 1871, television is in virtually every home, as is radio and electricity.
However there is a rush for this new technology in Europe. A newly created German Empire, a chaotic French third republic, a Superpower Britain, and a stagnating Russia all try to gain this new technology. Britain's entire fleet is now obsolete due to the Union's small but powerful navy.
Britain draws up plans for its own battleships, followed by France, Russia, and Germany. At roughly the same time the Union launches its first home built and also the world's first independently built battleship, the USS United States, Britain launches HMS Nelson, a battleship based on the HMS Hood from our timeline.
France and Russia are not far behind, launching La Paris and Tsaritsyn at roughly the same time. By 1890, the world launches a reclassification.
Battleship- Large, heavily armored, with guns ranging from 11-18 inch. (based on Bismarck)
Battlecruiser- Smaller, but with similar armor, but more speed then a battleship. (based on Scharnhorst)
Heavy Cruiser- Guns 10 inches plus, with high speed. Virtually a small battlecruiser based on Admiral Scheer)
Middle Cruiser- Guns 10- inches, with similar speed, weight, and armor. (based on Prinz Eugen).
Light Cruiser- Small, light, fast cruisers designed as cheaper versions of Heavy Cruisers (based on a US design).
Destroyer- Small light vessel designed to escort commerce or destroy torpedo boats.
By the 1890s, the US Navy was the largest in the world, with 22 Battleships, 18 Battlecruisers, 32 Heavy Cruisers, 40 Middle Cruisers, 56 Light Cruisers, and 186 Destroyers. The reason was because Britain's rush to build up ships to match the US, as well as more, was seen as a threat, and given anti-British sentiment at the time, America and Britain entered a naval arms in the 1880s.
Britain at that time had 16 battleships, 12 Battlecruisers, 23 Heavy Cruisers, 30 Middle cruisers, 36 Light Cruisers, and 100 destroyers. This was primarily due to Britain's smaller industrial strength then the US. Germany had entered in the 90s, and had 14 modern battleships, 14 modern Battlecruisers, 20 Heavy Cruisers, 28 Middle Cruisers, 30 Light Cruisers and 100 destroyers.