Show her this video.
Tell her, the law only affects the defender.
The attacker can bring large mags, or many smaller ones.
Mr. Law Abiding Citizen (average, not mr, tactical) usually has the one mag. Or a second, sitting in the safe.
[video=youtube;7F1nPSNnaBo]https://www.youtube.com/watch?v=7F1nPSNnaBo[/video]
That is a good video, I hadn't seen it B4 .....