The Confederacy scores a decisive victory at the Battle of Gettysburg, effectively destroying the Army of the Potomac.
Without anyone standing in his way, Lee marches east toward Philadelphia.
The defeat at Gettysburg is devastating for the Union while being a boost in morale for the south. The Draft Riots are much more violent and Congress considers impeaching President Lincoln for his poor handling of the situation.
By 1864, the Union is forced to make peace with the Confederacy under pressure from the United Kingdom and the American populace.
With frustration of Byrd's policies, Texas declares its independence from the Confederacy in 1945. The United States immediately recognizes it. However, uses it as a client state to fight the Confederates.
Uprisings are somewhat common in former Canada and the Confederate States, with nationalist groups fighting for independence from the United States.
Northern Maine would be annexed by the British after the Kentucky War. However, with the rest of Canada, it would be reabsorbed into the United States.
The unified identity of being "American" wouldn't come around until World War I. However, the belief would begin after the Kentucky War.
Germany is the most powerful nation in all of Europe.
The OTL United Kingdom would be fractured after 1945, with England, Scotland, and Ireland all being independent.
The cities of Paris, St. Petersburg, London, Portsmouth, and Oxford, were completely destroyed in 1944-45 after the Germans led several nuclear attacks on the Entente.
After the Kentucky War and the formation of the German-American Alliance, the United States military begins to adopt some Prussian/German military tactics and principles. The American military uniforms are much more like the German uniforms in OTL during the World Wars.
The Confederate military uniforms are similar to the British and French uniforms of the World Wars (and to an extent the OTL American combat uniforms)
The atomic bomb is developed and utilized earlier than OTL, with Albert Einstein helping the Germans build a bomb by 1944.
Europe is much more Semitic due to no Holocaust. However, antisemitism is still very prevalent in the world.
Islam is much more prevalent than OTL and has fewer extremist organizations.
Equal rights for blacks are achieved earlier than OTL after the revelations of the Extermination, beginning in the United States. The U.S. encouraged the rest of the world to do the same.
Fascism (not to be confused with Restorationism) would still remain as a prominent political ideology as Italy and Spain would remain Fascist dictatorships for a fairly long time. Japan would take up Fascist principles. However, would never call itself Fascist.
The Cold War continues to this day between the United States and the Japanese Empire.
The War on Terror would be fairly different from OTL. The United States, along with Germany and Russia, would still invade Afghanistan after 9/11. The Mujahideen would be backed by the U.S. and its allies during the Indian War in Afghanistan and still institute an Islamic dictatorship. During *year coming soon*, the United States and its allies would invade Sudan to stop ethnic genocide in Darfur, beginning the War in Sudan.