The running would not have been that bad in decent weather, but the campus was absolutely frigid, and the wind off the lake was cutting. A penguin would have had trouble out there. We ran through snow, marched through snow, and made our way to classes through snow.

In that first week, while we were trying to avoid freezing to death, they instilled in us three words which have been with me ever since. Honor, Courage, Commitment, the motto of the United States Navy, the core values that immediately became the ideals we all lived by. I can remember to this day an instructor telling us, “What you make of this experience here at Great Lakes is what will make you as a person.” He was right. I hope.

In the second week, they put us through the Confidence Course. This is designed to simulate emergency conditions in a U.S. Navy warship. They taught us to be sharp, self-reliant, and, above all, to make key decisions on which our lives and those of our shipmates might depend. That word: teamwork. It dominates and infiltrates every single aspect of life in the navy. In boot camp, they don’t just tell you, they indoctrinate you. Teamwork. It was the new driving force in all of our lives.

Week three, they put us on board a landbound training ship. Everything was hands-on training. We learned the name of nearly every working part of that ship. They taught us first aid techniques, signaling ship to ship with flags (semaphore). We spent a lot of time in the classroom, where we focused on navy customs and courtesies, the laws of armed conflict, shipboard communication, ship and aircraft identification, and basic seamanship.

All this was interspersed with physical training tests, sit-ups, sit-reaches, and push-ups. I was fine with all of those, but the one-and-a-half-mile run in that weather would have tested the stamina of a polar bear. They told us anyone who failed could come back and take it again. I decided I would rather run barefoot across the Arctic than take it again. Gave it my all. Passed, thank God.

During week four, we got our hands on some weaponry for the first time — the M16 rifle. I was pretty quick with that part of the course, especially on the live-fire range. After that, the navy concentrated on which path through the service everyone wanted to take. That was also easy for me. Navy SEALs. No bullshit, right?

The firefighting and shipboard damage-control course came next. And we all learned how to extinguish fires, escape smoke-filled compartments, open and close watertight doors, operate the oxygen breathing apparatus, and move fire hoses around. The last part was the worst — the Confidence Chamber. You get in there with your class and put on a gas mask. Then someone unleashes a tear-gas tablet, and you have to take off your mask, throw it in a trash can, and recite your full name and Social Security number.

Every single recruit who joins the navy has to endure that exercise. At the end, the instructors make it clear: you have what it takes. There’s a place in the navy for you.

The final task is called battle stations. Teams are presented with twelve situations, all of which have been addressed during the previous weeks. This is where they grade the recruits, individually and as teams. When you’ve completed this, the trainers present you with a U.S. Navy ball cap, and that tells the world you are now a sailor. You have proved you belong, proved you have the right stuff.

The following week, I graduated, in my brand-new dress uniform. I remember passing the mirror and hardly recognizing myself. Standing tall, right there. There’s something about graduating from boot camp; I guess it’s mostly pride in yourself. But you also know a lot of people couldn’t have done it. Makes you feel pretty good. Especially someone like me, whose major accomplishment thus far had involved hurling some half-drunk cowboy out of an East Texas bar and into the street on his ear.

After I graduated, I flew immediately to San Diego, headed to Coronado Island and the navy amphibious base. I made my way there alone, a couple of weeks early, and spent my time organizing my uniforms, gear, and rooms, and trying to get into some sort of shape.

Most of us had lost a lot of condition at boot camp because the weather was so bad. You couldn’t just jog outside and go for a run because of the blizzards and the deep snow. Perhaps you remember that very brave guy who made the journey to the South Pole with the Royal Navy officer, Robert Falcon Scott, in 1912. He believed he was hindering the entire team because of his frostbite. Captain Oates was his name, and he crawled out into a raging blizzard one night with the immortal words, “I am going outside now. I may be gone for some time.”

They never found his body, and I have never forgotten reading his words. Guts-ball, right? Well, going outside at Great Lakes would have been a bit like that, and almost as brave. Unlike the gallant captain, we stayed by the heater.

And now we were going for runs along the beach, trying to get in shape for the first week of Indoctrination. That’s the two-week course known as Indoc, where the SEALs prepare you for the fabled BUD/S course (Basic Underwater Demolition/-SEALs). That one lasts for seven months and is a lot harder than Indoc. But if you can’t get through the initial pretraining endurance test, then you ought not to be in Coronado, and they don’t want you anyway.

The official navy literature about the reason for Indoc reads: “To physically, mentally and environmentally prepare qualified SEAL candidates to begin BUD/S training.” Generally speaking, the instructors do not turn on the pressure during Indoc. You’re only revving up for the upcoming trial by fire.

But they still make it very tough for everyone, officers and enlisted men alike. The SEAL programs make no distinction between commissioned officers coming in from the fleet and the rest of us. We’re all in it together, and the first thing they instill in you at Indoc is that you will live and train as a class, as a team. Sorry. Did I say instill in you? I meant, ram home with a jack-hammer. Teamwork. They slam that word at you every other minute. Teamwork. Teamwork. Teamwork.

This is also where you first understand the concept of a swim buddy, which in SEAL ethos is an absolutely gigantic deal. You work with your buddy as a team. You never separate, not even to go to the john. In IBS (that stands for “inflatable boat, small”) training, if one of you falls over the side into the freezing ocean, the other joins him. Immediately. In the pool, you are never more than an arm’s length away. Later on, in the BUD/S course proper, you can be failed out of hand, thrown out, for not staying close enough to your swim buddy.

This all comes back to that ironclad SEAL folklore — we never leave a man behind on the battlefield, dead or alive. No man is ever alone. Whatever the risk to the living, however deadly the opposing fire, SEALs will fight through the jaws of death to recover the remains of a fallen comrade. It’s a maxim that has survived since the SEALs were first formed in 1962, and it still applies today.

It’s a strange thing really, but it’s not designed to help widows and parents of lost men. It’s designed for the SEALs who actually do the fighting. There’s something about coming home, and we all want to achieve that, preferably alive. But there is a certain private horror about being killed and then left behind in a foreign land, no grave at home, no loved ones to visit your final resting place.

I know that sounds kind of nuts, but nonetheless, it’s true. Every one of us treasures that knowledge: No matter what, I will not be left behind, I will be taken home. We are all prepared to give everything. And in the end it does not seem too much to ask in return, since we fight, almost without exception, on the enemy’s ground, not our own.