USPSA is the United States Practical Shooting Association, which is the US member of the International Practical Shooting Confederation, or IPSC. It was founded in 1986 as a way to codify the pistol matches that were springing up across the USA.
IDPA is the International Defensive Pistol Association, and it was founded in 1996, as a response by some who felt that IPSC competitions were getting too far from the intended purpose. Namely, the founders didn't like the IPSC trend toward "race guns," or guns purpose built for competition, and felt that there should be a sport that required the use of normal carry guns, with stages based on more real world scenarios.
The debate continues today.
Serendipitously, I came across this interesting passage the other day:
The object of practical pistol skill is not to win trophies, but rather to stop fights. Muzzle brakes and reduced loads are backward steps and not to be regarded as progress. When we see the terms "race gun" and "carry gun" as representing two different instruments, we learn that some people at least have lost sight of the object of the exercise.This comes from none other than the founder of IPSC and its first president, Jeff Cooper.
Interestingly, he goes on.
It is important not to become dogmatic about this.Whoa. Dogmatic doesn't even touch some of the "discussion" I hear.
He concludes:
If there is a better way or a better weapon, let's have it. But I have not seen this developing in pistolcraft, at least not recently. Those of us who have studied the matter deeply understood this a good many years ago. We will change when we are shown why we should, but not until then.
In this light, the recent trend in USPSA toward the Production division is certainly welcome.
So, if you're serious about shooting, you should be competing, both to build defensive skills, and to do so in a stressful environment. It seems clear that it doesn't matter which sport you choose, as long as you keep your goals in mind. The rules may be different, but the goal should be the same.
If we get away from the original intent, however, we risk making it into something it isn't suited to be, and something it wasn't meant to be.