Uh, no they aren't. They are the armed forces, not the militia. The armed forces are governed by a different set of rules.
Title 10, Section 311 defines the militia. Paraphrasing, the organized militia is the National Guard and Naval Militia, and the unorganized militia is virtually every other male between 17 and 45 years of age.
Of course, that doesn't mean that we shouldn't have access to owning the same infantry weapons that the armed forces use.
That is the U.S. CODE, but NOT in the Constitution...
Nice try, but the people define the terms.