The really weird part of the timing of this is that the United States is moving more and more towards private enterprise space programs.
What would be the mission of this 'space force'?
In my opinion, one of the current, most important missions would be the protection of our satellites in space and work today. Russia has launched satellites capable of shooting down satellites with laser beams. They are currently already practicing on space junk. China too has demonstrated that they are able to shoot down satellites.
How do we protect the satellites that control our very existence?