You are so right about situational awareness and protecting yourself in public places. I had a bad situation last Sunday at a supermarket. It wasn't that busy but a queue was forming behind me at checkout. I had a trolly with a lot I didn't plan to get. The girl at till wouldn't start scanning until I had every item removed and there wasn't room to put everything on belt. This delayed checking out and a woman behind me got irate and angry I was slow moving my things, and suggested helping me but her hostile expression put me off. She then got angry and started bullying me, alleging I was to blame for being slow and had said something to cashier. It got horrible and manager didn't care. She then took out her phone to take a photo of me. I turned my back to her and got afraid, as she was being so irrational. I tried to complain to manager but he had little interest, so I left a full load of shopping worth a lot money behind and walked out of the shop. I complained next day to head office. I wasn't as calm as you. You are right about protecting your personal space but in my situation someone intruded on it and wouldn't give me time to remove my shopping. What a nightmare!