"Witnessing Tools"

Apparently, Evangelicals use symbols, know as "witnessing tools", to start conversations with the people around them with the goal of conversion. The famous fish symbol, seen on so many bumpers, is one, as are a myriad others. I've noticed this stuff, but I only thought it was the expression of the individual; I didn't know these had a name and an organized function. However, there is another analysis of them which makes sense by Fred Clark, wherein he sees them as instruments of contempt by their users:

   "The Jesus-fish on a car is not an invitation, but a declaration of tribal allegiance. It’s a signal that the driver of this car is an “Us” rather than a “Them.” And that Us-Them symbolism has far more to do with conflict than with any attempt at conversion. This is true as well of many of the other things we tell ourselves are “witnessing tools.” One one level, they may be intended as conversation-starters, but on another level they’re also intended as conversation-stoppers — as attempts to win some implied argument. They’re not really designed for evangelism. They’re just the graffiti and propaganda of the culture wars."

I have to say, I agree, considering the following as one example on a site selling t-shirts Clark lists. Yuck!