She was right to speak out, and her employer was within its rights to fire her. As long as she subsequently found a job at a company that comes closer to sharing her values, it sounds like a win-win.
Defence is one of the most vital sectors in a countries continued existence, coming just after food and water.
One could even argue that defense even precedes food and water at this stage also.
Imo its more acceptable and moral to work in the defence of your nation than to design increasingly intrusive data harvesting / advertising machines.
But as ever there isn't a correct answer and everyone is entitled to their opinion.