if you think it about it, 99.9% of the people out there, don't really carry ****, dont' really have any way to defend themselves in that instance. basically you are just depending on good will. fuuuuck that.
That is the rationale behind martial arts, which I'm not suggesting would have saved you, but a gun is not the magic answer, either. I think everyone should have the right to own firearms, but fwiw I don't like anything as a weapon that can be taken away and used against me, which is what is going to happen when you pull it out and don't kill everyone immediately. Even if you are a perfect shot (most people are horrible), an adversary can still mortally wound you before he dies of blood loss from gunshots. Other advantages to fighting with your bare hands are that they don't run out of bullets or jam; they are always exactly where you need them; and you avoid all of the legal consequences of shooting someone. If you had blown those three guys away, even if you didn't go to jail, their widows and orphans would sue you in civil court, which is a certainty because you have assets to take.
Glad you're ok. I think you did the right thing by not fighting back.