The United States is a major country during World War II consisting of 48 states. Its main military force is the U.S Army.
In the original game, the United States are mentioned in relation to the President Franklin D. Roosevelt and/or Truman who is mentioned offhand in the chapter ending descriptions in particular at the end of Episode 3.
It's also introduced in the official guides that B.J. Blazkowicz's country of origin is the United States, and its implied to be in Milwaukee, Wisconsin (while his parents were immigrants from Poland, he himself was born in the States, and thus a natural-born citizen). In addition its made a point that he is a United States soldier in the documentation, and various Nazi opponents make reference to this fact by calling him the American.
Spear of DestinyEdit
Franklin D. Roosevelt appears in the ending for the game and its two expansion packs within the White House in Washington D.C. to thank B.J. Blazkowicz for his successes at stopping the Nazis from using Spear of Destiny for evil purposes. The backstory for Mission Pack 2: Return to Danger tells of Hans von Schlieffen ("The Axe") and his troops attempt to invade the United States to steal back the Spear of Destiny, and take it to a secret Scandinavian Base. He was the only survivor.
By 1945 (when the story takes place), the U.S has had successful tests of atomic bombs during the Manhattan Project and has plans to soon use them to end the war.
The New OrderEdit
The United States is among one of the last few countries to fall to the German might.They surrender in 1948 after the destruction of Manhattan by an atomic bomb. The President announced it's surrender during a speech a day later. With Hitler giving a speech to his American Nazi supporters and Horton Ho 229 Jets flying overhead.
Soon after the Germans did a victory tour through the streets of the East Coast, and ordered soldiers to stand down and be issued work cards, to be redistributed into new labor. It's also known that they controlled New York, and most of the east coast up to 1960, and planned to rebuild Manhattan by 1965. They also demolished Mouth Rushmore to wash away the remnant of the old regime. Finally, they made the 4th of July from national day of the American to Victory Day or Liberation Day to celebrate the day they conquered American.
J states that the average white American "patriot" (including B.J.) would actually have fit-in with The New Order, and agreed with the Nazis, and most became enforcers for them after the U.S fell ("before the war you were the Nazis"). J, also mentions that the "The Man" (his name for the US government), "ran scared...mother-fuckin gave up...Nazi asked the Man to get down on his knees, and the Man was all too happy to pucker up, and start kissing Nazi ass, like it was the most natural thing in the world". That the Man started throwing its 'degenerates'/'undesirables' into the gas chambers, just like the Germans.
The game is vague as to the western states, one newspaper (no date given) suggests that resistance made it very hard for Germans to keep control of most of the United States, as most people took up arms and continued to resist the Germans, despite the Germans attempts to kill innocent civilians in retribution. There is no specific explanation as to the outcome of the resistance, but it may still be active because Nazi forces are spread wide and thin around the world to keep order. This is evidenced by the Kreisau Circle, which is active, even though it is in the heart of Nazi territory.
There are hints that perhaps as far west as Texas may still be relatively free. But these maybe areas where Germans may still have a frontline, although the main frontline is still in Africa by 1960. By the end of the game, it could be assumed due to the destruction of Deathshead and his compound, which dealt a devastating blow to the Nazi's war efforts and slowed down the war in Africa, the Nazi's grip on the world, including the United States, is slowly crumbling.
The New Colossus Edit
In 1961, it is shown that the Germans have a strong hold on the City of New Orleans, suggesting they control America's East Coast up to and beyond the Mississippi River. As of the game's events, Chicago has been destroyed, the Nazis control Alaska, and at least have a presence in California.
The events of New Colossus also give the full picture of life under the Nazis' rule for the average American citizen. In general, the life of most American citizens is highly oppressive since they have to endure curfews and both employments and marriages are being controlled strictly by the Ministry of Labor and Affair. Furthermore, personal privacy is no longer a luxury due to the populace being monitored 24/7 by drones. Freedom of speech has also been completely abolished since the Nazis purged all American media and press to replace it with their own propaganda machine to promote their lies and racial bigotry. The prime example is the Newspaper American Aryan Weekly newspaper. They also introduce Nazi versions of Captain American to brainwash the youth and the mass with the superheroes character with a thunder power called Blitzmensch who fights the super villain Uncle Sam or other Western-themed villains. All American people are being forced to learn German and read at least one chapter of the fascist Mein Kampf book every day. At the same time, any actions that involve questioning Hitler's childhood origin will be prosecuted harshly.
Based on the conversation of the citizen in New Mexico, the Nazis have a very strong base of support from white supremacists and hate groups like the KKK since they put all African American and LGBT people into concentration camps and reintroduced slavery back to the US, as evidenced by the fact that some wealthy white Americans can auction slaves in a legal auction. As a result, most of the free African Americans and LGBT people along with average white Americans plus progressive Americans take up arms to resist both the Nazis and the white supremacists to fight for their freedom and to liberate the US from the oppressive Nazi regime.
It is also noted that some Americans prefer the Nazis' rule over the US due to the fact that they prefer the culture of the Germans over the US. For example, an American woman was grateful for the Nazis having removing Jazz and Rock music from the mainstream media and a group of men praised them for ridding America of Hollywood's movie culture.
At the same time, most of the American are displeased with the Germans for Germanizing all American culture aspects by removing American iconic foods like burger or fried chips in favor of German foods like sausage or schnitzel.
Due to BJ's actions against the Nazis, his wanted poster is now placed in nearly every American city. While the Nazis brand him as terrorist, the majority of Americans from all races see him as a hero and symbol of hope and rebellion against the Nazis.
Although most of the US military factors were disbanded after the occupation, the large remnant of the US military still organizes resistance against the Nazis' rule.