Problem solved.
All I can say is that people have died from one punch. Take that for what it's worth.
The best answer I can give to scenarios like this is "depends".
From the article is sounds like the guy had plenty of time to break contact after he was punched. Why did he choose to draw his gun and stand there as opposed to simply turning around and leaving? Even if the attack continued he would be hard-pressed to make good hits without collateral damage in a crowded line like that.
IMO, given the details in the article, drawing was not the most appropriate answer.
We don't negotiate with terrorist that have several hostages and may kill them, why let a bully skip in line because he punched you? Letting bullies get what they want is why it was so easy for a couple of guys with box cutters to fly planes into the WTC.
No.Holiday Shopper Draws Weapon After Getting Punched - Gun News at Guns.com You are in a line and have words with someone that line jumped. He punches you. Do you draw???
We sure have a lot of bad azzes on INGO!