Been doing some work on the Class II powered armored suits worn by the United Nations Defense Force (made up of members from various branches from each other the world's militaries) for my Interplanetary War/Earth vs Mars story, Invasion Day.
First up the American Minuteman.

The Minuteman was developed just prior to the Interplanetary War and was still being field tested.

Using the latest advancements in SQUID (Superconducting Quantum Interference Device) array, the Minuteman is designed to be transform an individual soldier into a superior fighting force (although Armored Troopers are tr…

The Minuteman is powered by a high-density cryogenic refrigerator battery that while powering the suit for at least 2 and half weeks (although strenuous combat situations can lower this to one week) uses a cryogenic fluid to cool the battery's superconducting material.
The armor of the suit uses a combination of ring carbon titanium and SWDWNT (Single-Walled Carbon Diamond Whisker Nanotubes) to help protect the operator. Strength amplification is provided by a combination of seromotors, hydraulic pistons, turbines, and electroelastic fibers.

The Interplanetary War involves after Mars has forced the other Solar System colonies to unite with it against Earth colonialism and imperialism. However, the war soon takes a turn when the Martian Revolutionary Liberation Front changes into the Unified Martian Regime who desire the total destruction of Earth (similar to the Settlement Defense Front in Infinite Warfare).

I'm using some ideas for the colonies: Like floating cities for Venus, underground and above ground ones for Mars, sub-surface city for the Moon near the Sea of Tranquility (actually this becomes Tranquility City) and the…