I love the military of the United States.  There are currently five branches: the Army, Marine Corps, Navy, Air Force, and Coast Guard.  President Trump just announce a new branch called the Space Force yesterday.
I heard about that! Do you think the Space Force will fight aliens? Or attack countries in space?
LOL.  My guess would be a space fight against other countries.  The President is the commander-in-chief of all our armed forces.  And the Department of Defense really impliments his plans.  
It is really interesting to me how the President automatically becomes commander-in-chief, even without any military experience.
That is part of the role of the President.  Thankfully, though commander-in-chief, most Presidents rely on their military leaders to assist in planning and give direction.  Ultimately, however, all decisions of the military come down to the commander-in-chief  
What else can a commander-in-chief do?
Commander-in-chief
A commander-in-chief, sometimes also called supreme commander, is the person that exercises supreme command and control over an armed forces or a military branch. As a technical term, it refers to military competencies that reside in a country's executive leadership – a head of state or a head of government.
Often, a commander-in-chief role if held by an official, need not be or have been a commissioned officer or even a veteran. Such countries follow the
, a cutoff point is determined.
Procedures Eligibility.
The branches of service eligible for Space-A travel are:
- United States Navy
- United States Marine Corps
- United States Army
- United States Air Force
- United States Coast Guard
- United States Public Health Service
- National Oceanic and Atmospheric Administration
Procedures Space-required versus space-available.
Space-A travel is not without its pitfalls. Unlike traditional commercial air traffic, military flights are not always assigned predictable takeoff times