Next to purchasing a quality firearm, the most important thing a defensive shooter can acquire is professional training. Actually, if you wanted to say that professional training was more important than the quality of the defensive firearm, I wouldn't argue with you.
There is this persistent myth that Americans–especially the men–are all natural-born good shots. I suspect that this is a holdover from our frontier history and, if our enemies abroad want to believe that, it's okay with me. It is just important that you and I know it is a myth and nothing more. Nobody is born a good shot. Developing good defensive shooting skills takes time, good training and lots of practice.
Professional training gets us started in the right direction with a minimum of time and expense. It smooths edges and helps a person learn quickly. And developing good defensive skills quickly is really important when your life is at stake. Being serious about developing good defensive skills, we should be seeking quality training at every opportunity and not waiting for the perfect invitation.
In addition, one should always keep in mind that the ability to shoot quickly and accurately is a rapidly diminishing skill. That means you can forget a lot in a hurry. Even if we practice our skills regularly, we will quickly begin to forget many of the things our instructor taught us during school. This is the reason I try to book at least one training class per year and would book more if my budget could handle it. And I tell you this in light of the fact that I was a Texas peace officer for 30 years and was involved in some deadly encounters. I still need regular training, and you probably do, too.
If I had my way, there would be no carry licenses and all good citizens could carry defensive firearms at all times. We owe it to ourselves and our loved ones whom we seek to protect to be as good and as safe with our defensive firearms as humanly possible.
Don't wait for someone to drag you to a professional training class. Do it because it is the right thing to do. You won't regret it.