At least she's previously been Minister of State for the Armed Forces and is a Royal Naval Reservist, so has some background in defence matters. Daughter of a former Para too.
Made I chuckle too (from Wiki):
When receiving The Spectator magazine's Parliamentarian of the Year award in November 2014, Mordaunt said that she had delivered a speech in the House of Commons just before the Easter recess in 2013 on poultry welfare so as to use the word "cock" as a forfeit for a misdemeanour during Naval Reserve training. Mordaunt used the word "cock" six times and "lay" or "laid" five times. Following her comments, she was accused by Labour MP Kate Hoey of trivialising parliament.