The US will conquer the world after starting WW3 once it's laser missile defense systems and radar have fully upgraded and fully deployed.

With the use of AI training we could develop missile defense systems with an accuracy rate of 100% capable of taking down all missiles coming at it. With additional radar and hypersonic missile detection upgrades, along with laser defense systems that can shoot down these missiles in the atmosphere, it becomes possible for the US to survive both the first and second wave of a nuclear strike.

In such a scenario for the first time since 1947 countries are once more in a position to declare war on each other without fear of the world ending.

In such a scenario the US would obviously invade all of it's competitors and beat them at war. It would first destroy Cuba, then Russia, and then China. Once it has defeated these nations it will invade Europe to finally take all the white people under a single umbrella.

Australia and New Zealand will willingly join out of fear and respect for the US.

After this the US will invade South America and conquer the entire continent.

Once it has done all this it will build a border wall after Kanye becomes president. The border wall would extend all the way from Finland's border down to Greece, then all the coastlines of South America. It will go around the world and build a wall around Japan and South Korea and Taiwan.

All sea travel will be banned. Only transportation of goods will be permitted.

After this the US will have a population of 2 billion people making it the largest country in the world.

The US will own 50% of the world's land.

The US will have an immigration system to acquire cheap Chinese labor; no citizenship.

Any space programs that launch objects into the orbit outside of the US will be shot down.

The border wall will extend all the way through the middle of the ocean.

This state of affairs will remain for the next 3 centuries.