3 points
You do what the police do, and provide a proportionate response.
A gun is only to be used if you are in imminent danger of your life. A robbery is arguably not that, unless they’re trying to steal your organs or prostheses.
There’s a reason your average supermarket security guard doesn’t immediately whip out the Mini-Nuke the moment they see a shoplifter.
There’s also something to be said about the place you’re living in, where you’re to be terrified of stabbists and robberers the moment you step out-of-doors. Do you live in a hive of scum and villainy?