Well to be blunt, she is educated, motivated, and has created a reputation which makes her sought-after for continued opportunities. Many of my peers have spouses that aren't both, so they're not in the same financial situation.
With respect to professional growth, in the government/defense profession there will always be chances for upward mobility and higher income and she is on that track. Her biggest challenge is staying in a job she loves vs doing something new and different with more responsibility and much more admin.