In my case, maybe I’m hearing “Thank you for your service” because I’m an old guy, often wearing a faded old Navy ball cap or T-shirt. But I think that sentiment is popping up everywhere. I’m always surprised when I hear those words, and I always appreciate them.

Today is Veterans Day, and we’ll surely hear it a lot. One way we veterans can react is to simply accept that we earned the compliment. There are 15 million or so U.S. military veterans kicking around today, and we all donated at least a few years of our lives. We volunteered to serve, we left home, we put on the uniform, and we did what had to be done to keep this nation safe.

But it occurs to me that the thanks should go both ways. While we veterans naturally like to receive thanks from the nation for our service, we should also be thanking the nation for the opportunity to repay, in small part, the priceless benefit of U.S. citizenship and to do our part in keeping our homeland safe.

The grand bargain of military service is essentially this: Those who join make an unconditional commitment to endless training, 24/7 working hours, extended deployments away from home and family, and very real occupational hazards — including going to battle for our country if need be. In essence, we commit to trusting our leadership and following their orders, regardless of political views. In return, we earn the opportunity to serve the country we love and to benefit from the immeasurable life experience of service in the world’s finest armed forces.

As I recall, leaving home at 17, three weeks out of high school, headed for the U.S. Naval Academy, I surely had patriotic thoughts about serving my country. But I was also fulfilling a lifelong dream and embarking on what I expected to be a great adventure. Looking back now as an 81-year-old, I realize that the U.S. Navy certainly held up its part of that bargain.

In the military, that high adventure comes in a heavy stew of hard work and critical life lessons. Examples:

• Do you wonder how you would stand up to a challenge that seems utterly insurmountable? Expect that circumstance to crop up again and again — and see how much you grow on each occasion.
• Do you sense a need for order and discipline in your life? Boot camp will provide exquisite clarity on that concept.
• Strive for physical fitness? You’ll find that it’s demanded across the board, and to extraordinary levels in elite units like the Navy SEALs or Army Special Forces.
• Do you like jumping out of planes? No problem — that can be arranged.
• A need for speed? Exhilaration? Amusement park rides are OK, but for the real thing, try to work your way into Navy, Marine, or Air Force flight training, and someday you may find yourself in the cockpit of a high-performance jet. Strap in hard. And if you have difficulty overcoming your fears, imagine landing that jet on the pitching deck of an aircraft carrier on a dark night in heavy seas.
• Like the great outdoors? Wind in your face? Maybe some salt spray? Give the U.S. Coast Guard a try, famous for sending ships out to sea in weather so foul that everyone else is heading for shelter.
• In our military, you will learn what “on time” really means. In the Navy, it means being early — being late is intolerable. Need a refresher on preparedness? Accountability? Teamwork? Those are the daily diet of military life.

If, like me, you follow politics closely and grow weary of politicians who talk about the importance of unity but keep driving us apart, you wish they could spend a few months at sea on a submarine. Being literally “all in the same boat” erases all confusion on that subject.

Of course, the promised adventure of military service is only half of the bargain. The oath we all took was deadly serious, and we can’t sugarcoat the hard reality that military service is at times a perilous profession, certainly in wartime but also in peacetime. Inevitably, some die in the line of duty, and others suffer serious physical and emotional injuries that last a lifetime. Every one is a tragedy.

The price paid by those service members and their families is incalculably high. We can only admire and thank them forever for their unconditional commitment to serve, we can help their families, and we can elect leaders dedicated to keeping our nation out of war. In the outside world, the phrase “never forget” is often used casually. Veterans never forget.

But I would also wager that nearly all veterans consider their own military service as a central life-building block. They remember the good and the bad, and they know that the life lessons of both are priceless. And for all the grumbling about the burdens and discomfort of military life, most veterans will tell you that the experience was invaluable and that they wouldn’t trade it for the world.

Military service is essential to our national defense, and it transforms the lives of many who serve — to their lifelong benefit and also to the benefit of our country. I cannot think of a better way to jump-start adult life as a citizen of this great nation.

God bless our nation, and God bless those who keep it safe.