It is now about fourteen months since, after receiving my second death threat, I started carrying a firearm almost constantly. This experience has taught me a few truths, some merely amusing but others with larger implications.

The major lesson: people are amazingly oblivious to what they don’t expect to see. When I carry using a belt holster (not my only method), I watch peoples’ eye movements and facial expressions for this pattern: eyes going to my right hip, momentary startlement or an increase in tension. This would mean the shirt I’m wearing flapped over the pistol butt has ridden up and it’s exposed. But, in fact, with only one exception that I’ll get to, I have never seen this. On the other hand, there have been occasions when I’ve noticed by touch that the weapon was exposed, or my wife has told me it’s showing, and nobody around me gives any sign of having noticed.

The one exception: a teenage girl in my regular gaming group with a minimal-brain-damage syndrome that isn’t autism but gives her an autist-like tendency to notice details other people miss. She did startle. I explained, and she ceased being bothered.

The gaming group taught me another lesson: never, ever, ask permission to carry or give others an option to deny it – just do it and refuse to discuss the matter. I won’t reveal the details, because doing so would poke a small hole in my security plan. But I learned this one the hard way.

And about that security plan: carrying a firearm is nearly useless without very specific kinds of mental preparation. It’s not just that you have to think through large ethical issues about when to draw and when to fire (equivalently, when to threaten lethal force and when to use it). You also need good defensive habits of mind. Carrying a firearm is no good if an adversary wins the engagement before you have time to draw.

The most basic good habit of mind is maintaining awareness of your tactical environment. From what directions could you be attacked? Is there a way for an assailant to come up behind you for a hand-to-hand assault, or to line up a shooting position from beyond hand-to-hand range where you couldn’t see it? Are you exposed through nearby windows?

One advantage I had going in was reading Robert Heinlein as a child. This meant I soaked up some basic tactical doctrine through my pores. Like: when you go to a restaurant, sit with your back to a wall, preferably in a corner, in a place with good sightlines but not near a window. When you sit down, think about possible threat axes and which direction to bail out in if you have to.

Advice I’ve gotten from people with counterterrorism training includes this lesson: watch your environment and trust your instincts. Terrorists, criminals, and crazies don’t tend to blend in well even when they’re trying. If someone nearby looks or feels out of place in your surroundings, or behaves in a way not appropriate to the setting, pay attention to that; check your escape routes and make sure you can reach your weapons quickly.

How careful you have to be depends on the threat model you’re planning against. I’m not going to talk about mine in detail, because that might compromise my security by telling bad guys what expectations to game against. But I will say that it assigns a vanishingly small probability to professionals with scoped rifles; the background culture of both Iranian terrorists and their Arab proxies makes it extremely difficult for them to train or recruit snipers, and I am reliably informed that the Iranians couldn’t run professional hit teams in the U.S. anyway – too difficult to exfiltrate them, among other problems.

This, along with some other aspects of the threat model I won’t discuss, narrows the range of plausible threats to something an armed and trained individual with good backup from law enforcement has a reasonable hope to be able to counter. And the good backup from law enforcement is not a trivial detail; real life is not a Soldier of Fortune story or a running-man thriller, and a sane security plan uses all the resources available from your connections to the society around you.

So here’s another lesson: if you’re going to do anything that might piss off violent fanatics, make friendly with your local cops. Fortunately the ones in my town already like me. In truth, I think they’re kind of jazzed by the thought that they get to be second-hand involved in an international intrigue. Hackers and tyrants and terrorists, oh my!

Let ’em have their fun. I, being in the crosshairs, have to be more cold-blooded than that; hero fantasies could get my ass killed if they distract me from situational awareness and all the little low-level safety practices that go with it. In fact, it’s fair to say that the firearm I carry functions largely as a tangible, ever-present reminder of my need to maintain the alertness and mental stance that increases my chances of surviving a clutch situation. As a combat instructor I know puts it, “The mind is the first weapon”; it has to point before the gun can be aimed.

Since I am, alas, no longer actively involved in trying to subvert the mullahs’ regime, the odds I’ll have to cope with terrorist action are gradually dropping over time (not that they were ever very high; I never flattered myself with the assumption that I was a priority target). I feel less need to carry than I did fourteen months ago. But I also feel less need to stop. I’ve learned how to deal with the minor inconveniences, and developed habits that integrate constantly carrying a weapon with the rest of my life.

And it’s not only my own life that these habits may save. “When seconds count, the police are only minutes away.” Intervention by armed civilians on the spot aborts hundreds of crimes a year in the United States, and thousands more could be prevented if there were more of us. Carrying is not just a survival tactic for me; it’s a service, a net benefit to my neighbors and my nation and my civilization, and I feel good about that.