The riots that are now commonplace following any police shooting would look like this to you.
Living in a world of cocked mousetraps is frightening. Now that it's starting to happen reliably (Milwaukee, Charlotte, whatever), it's pretty apparent that the progressives have gotten everyone primed through racial grievance-mongering. Who knows where it's going to happen next. Not many Confederate flags in Milwaukee, so don't think being north of the Mason-Dixon line is going to save you.
The analogy works further as the original ping pong ball, the cop, isn't trying to set off a destructive chain reaction. It's just doing what ping pong balls normally do. In fact, in the absence of the cocked mousetraps, i.e. the racial grievance culture, a falling ping pong ball would only disturb a few of the other ones.
Finally, anyone miniature wandering around in the enclosure has nothing to do with any of it. They're just caught up in the maelstrom that wasn't there yesterday, but today is sweeping through the city.
Just a silly metaphor that popped into my head. Enjoy?