Getting taken by surprize always puts the defender at an immediate disadvantage. I constantly have people ask me for cigarettes, money, "a light", directions etc. Some people unknowly and out of social habit try to get way too close and squaring face to face.
When I spot someone making a beeline for me, or someone already quite close throws up a flag, I always pivot so as to keep them at about 9 o'clock when they close in. This nearly always brings them to a dead stop, as they realise I am unsure of their intentions, and ready to do something
they are not sure of. Although some will further involuntarily or otherwise move to square off, once they have moved around a half or three quarter circle or so, and I have stepped back if necessary to maintain a step or two difference, it does dawn on them.
Never let someone making a beeline for you walk up and get within strike/grab reach not requiring at least two full steps forward if possible. When someone does walk up on you or otherwise get your attention - do not neglect what and who else is going on around you. Sometimes the conversation runs;
"that's close enough thanks ......"
"huh? .. I ..."
"I can hear you just fine - what do you want?"
"Oh, I'm sorry (eying me nervously) ... I am looking for _____________"
Don't allow yourself to be drawn into a complete stranger getting your trust through a clever and protracted conversation. They may be waiting for you to drop your guard for just a few seconds.
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