Thank you for answering.
The problem with your argument is that "It keeps them from occurring" is the dictionary definition of "preventing."
Put it this way: Assuming defensive gun use prevents, say, a million incidents from becoming crimes, per year. (I'm making that number up, for illustration.) That means that if there was no defensive gun use, there would be one million more crimes on our books. That means that the presence of guns, of which we have a LOT, saves us one million crimes.
Which would be great, except that we already have higher crime rates, violent crime rates, firearm crime rates, and violent firearm crime rates than any other developed nation, by far. The "defensive gun use" argument is then saying that, if not for them, our crime rates would be *even higher*.
Why would our developed nation have crime rates be inexplicably in the stratosphere, if not for the most obvious and prominent difference between the US and every other nation—the gazillion guns?