[Michael Michael]

When both parents are U.S. citizens, and one is active duty personnel, and the spouse is a military dependent, then the UCMJ considers their child to be a natural born citizen regardless of where the birth takes place.

How does the UCMJ manage to trump the Constitution?

[Cyropaedia]

Because the military operates under its own official jurisdiction via the UCMJ. Military personnel do not have the same rights as civilians. But it works both ways with regards to exemptions.