bold statement - correct. otherwise you roll the dice. if youd like to that its a free country, just don't be surprised when you end up like zimmerman, or like my buddy who did time for his bar fight incident.
the point of the neighborhood watch is to alert police to suspicious activity, not engage a suspicious person. if you actively see someone break into a house or assault someone its a bit different. no point in approaching someone walking down the street. what do you expect to gain from that? you think they are going to say, "well yes sir, i was about to rob a place, thanks for stopping me?" either the person is up to no good and therefore is going to cause you some trouble you don't want, or they are simply walking down the street. either way, approaching them and talking to them won't necessarily tell you anything, but it may get you in trouble. watch from a very safe distance until the police arrive.