Ok, it's clearly time for the OP to chime in again....... and that's me.
Friends, I kindly request that you read, AND PAY ATTENTION TO all of my posts before commenting any further. Look through the entire thread as clarifying comments were posted.
It wasn't that someone was just walking behind me. That happens on a trail. I am not overly paranoid, and I can promise that in that, situation any of you would have felt like your personal space was violated. I rather enjoy talking to people I meet on the trail, and I have met some really interesting people from all over the world as a result. The fact that I do that reinforces that I am not inherently fearful of people, just warry of the ones I don't know.
In case some people refuse to go back and read, as usually happens, let me summarize.
I encounter three guys at a remote trail head parking lot.
They seem friendly enough, and we are all giving each other room.
As I move away from my truck and toward the trail I stop 20 feet away from all three and chat with them, and they innitiate the conversation. Things are still friendly.
Abruptly, one of the three circles around me in what appears to be a cool down walk. However, the time it took him to suddenly walk behind me is short. Time from standing 20 feet in front of me to circling around behind me is about 4 seconds, so this wasn't just a casual stroll speed. INot running, but moving quick enough that it seemed out of place that he suddenly felt the need to stand behind me, and it seemed like he was deliberately trying to position me between him and his friends. Keep in mind, this is an empty parking lot out in the woods off of a gravel road. There is no one else around and he suddenly feels the need to stand that close, and directly behind me.....
Now he is 5 or 6 feet directly behind me, and out of my sight...... I'm sorry, but anyone who wouldn't be uncomfortable with that action by a stranger in those circumstances is going to end up in a bad position some day, and if you wouldn't feel the need to have all three people in your sight, then you might as well leave your gun home, because if you aren't going to pay attention to odd behavior, you will never see a threat coming, and you will not have a use for the gun..... Your awareness is your first, and hopefully only used line of defense.
The bottom line, his actions were out of place, seemed a bit fishy, and made me really nervous, and if you think it wouldn't make you nervous, then you aren't comprehending the scenario............ or you are just really trusting. Sorry, I can't explain it any more clearly than this.
The botttom, bottom line. I don't think he meant anything by it. I'm 99% sure he just was't paying attention, and meant nothing by it. I DID NOT SAY "That is a good way to get a gun pulled on you!" THAT IS WHAT WAS GOING THROUGH MY MIND, AND WHAT I WANTED TO SAY. It is not what I would have said. I agree with everyone that SAYING that would have been a bad idea, and could reasonably be percieved as a threat. Saying that would have been a big mistake.
The reason I would say anything is to point out to him that his actions could be easily misinterpreted, and could make someone feel the need to get defensive. The idea would be to tell him, so he didn't accidentaly put himself in a situation where someone less level headed than I would do something stupid like drawing a gun on him. AT NO POINT DID I CONSIDER TELLING HIM THAT I WAS GOING TO SHOOT HIM OR DRAW A GUN. So if that's what you got out of my statements, then I was not clear, or you did not read thoroughly. Threatening someone is never ok. Saying anything would have been inappropriate, unless I moved out of that sitaution and he attempted to reposition himself behind me again. We all agree on that. SAY NOTHING!!!! We seem to have a consensus! Holy crap! There's a first time for everything!
On personal space: It is a relative thing. Everyone has different sized bubbles. I believe that for most people, the size of your bubble increases as you are in wide open surroundings, and decreases when in a crouded situation. If I'm in an airport, I don't expect you to stay a minimum of 5 feet away or anything. That is an unreasonable expectation. However, when outdoors in an open environment, and there are 4 people there 1 of wich is not a member of your party, and you are able to hear each other without a problem, I do expect you to not suddenly walk behind me and stand around within grabbing distance. If I did this, I would expect the person to tell me to stay back. If you disagree with this statement, then I advise you to rethink how you interact with strangers, as eventually you are going to piss off the wrong person.
Personally, if I had asked the guy to back off a bit and he refused, that would tell me he had ill intentions, or was unbalanced, and I need to get out of the situation. I would leave. If he was intent on maintaining his proximity to me while I was trying to leave, he would have a gun pointed at him real quick, and if he made the wrong move he would have a .45 cal hole in his chest real quick (though I suppose that day, it would have been a .357 cal hole). At that point, I'll deal with the legal ramifications. If you are that close to me and refuse to back off, I don't care what your intentions are, I don't care if you have a weapon, I don't care if you intend to give me a million dollars, I am assuming in that situation that you mean me harm. I have every right to ask a person to not do something that is violating my space and creating a percieved threat. If they refuse, it is my job to do whatever I can to get away from them without doing them harm, if I can not escape and I believe they mean to do me harm, I will draw, if the natural instinct of fear doesn't cause them to back off at that point, then there is something very wrong with them. These types of decisions will happen in an instant, and I would do my damdest to try and get anyone I shot on an ambulance and to a hospital.
If any judge disagreed with my logic in that last scenario, I'll see you all in 20 years I guess. That is JMO on personal space, and my personal way of navigating life. If something feels fishy, get out. If you can't get out, go defensive. If being visibly defensive doesn't change the demeanor of the person you feel the need to defend yourself from, then pull the trigger, and get a lawyer, because you will need one even if you are in the right.