I spent last Friday morning on hallowed ground.

I was at the National Cemetery in the Vicksburg National Military Park taking pictures of flags.

Let me be more accurate. I was supposed to be taking pictures of people placing flags on the almost 18,000 graves in the cemetery, but the volunteers’ labors concluded just before I arrived, and in true photographer fashion I began making lemonade out of the lemons I found. The result was the photo of a solitary flag by the marker of an unknown U.S. soldier; a man whose name, according to the legend on the Tomb of the Unknown Soldier in Washington, D.C., “Is known only to God.”

The cemetery by itself is an interesting place, with its almost 18,000 markers and headstones spread across the landscape and the rows of flags accenting them make the scene impressive.

It’s enough to make you think about the soldiers whose lives are now represented by a piece of marble — some holding a number; some with a name. I often wonder what kinds of lives these men lived and what compelled them to take up arms and in some cases go to war against a close friend or relative. Was it to preserve the Union? Free the slaves?

For the men buried in the section for the U.S. Colored Troops, the motivation was to fight for their freedom, since many members of the USCT were runaway slaves.

But I wonder about the veterans who lost their lives in America’s other wars. For World War I and II, the motivation was to fight against tyranny and stop a potential threat to the country.

In World War II, some men like my father, who was in the National Guard, were called up under a mobilization order they President Franklin Roosevelt. Others enlisted after Pearl Harbor out of a sense of patriotism.

But what compelled men to join a service branch to fight in Cuba during the Spanish-American War? What about Korea? Vietnam?

There will always be the question of service and we must remember that some men who fought in the Civil War, the world wars and Korea and Vietnam were drafted, whether they wanted to serve or not.

But in the end, the motive for serving is immaterial. Our veterans, living and dead, did their duty and served. Some may have done it reluctantly while others went willingly. And those who died made the ultimate sacrifice; they weren’t losers, they weren’t suckers.

If you think that, or if you want to have a better appreciation for those men and women to serve, go out to the National Cemetery and walk around, read the placards and look at the rows of markers and do as I did — think about the people buried there.

I went to the cemetery on an assignment last Friday. I learned a lesson in history.