I may get blasted for this, but I can handle it, LOL..
They will eventually have to be on their own. My son is a martial arts student and I have no fear of someone trying to get him. He knows EXACTLY what to do. He has trained on how to handle any and all situations. Emotional and physical. Being a survivor myself, I was adament about him being able to deal with any kind of emotional or physical attack.
To me, that's a better answer then never leaving them alone, if they are mature enough to handle of course. They could be in the grocery store and you go down one aisle, them another, and someone try to grab them....I could list you a thousand scenarios, what makes you think you can protect them more than you can, expecially if they are bigger than you ....I don't mean you personally Jeana, just making a point...he can protect me before I can him LOL
He is never online, so no predator access there, I just cover all the bases...if someone is going to try and get him, don't think they would succeed, I really don't.
Now, don't get me wrong, if I do leave him for a couple of hours, he must not leave house, I mean, some of the other little kids just run the streets, NOT my child. He is home, inside, doors locked, alarm on, yada yada. He doesn't even ride bus to school, but if he did, the potential is there for predator to snatch him there.
Can't watch them 24/7, I encourage ALL parents to teach your kids to take care of themselves. JMO