Today is Veterans Day, a day set aside to remember and honor the men and women who have fought in America's wars. It is celebrated on Nov. 11 because that is the day in 1918 that fighting stopped in World War I.

These days, not many star athletes serve in the military. One pretty famous exception was Pat Tillman, an Arizona Cardinals safety who joined the U.S. Army Rangers after the terrorist attacks of Sept. 11, 2001. Tillman died in April 2004 serving in Afghanistan.

Tillman volunteered to be in the military. That's how today's military works: People choose whether to join. Given the choice, most athletes (and most Americans) choose not to fight America's wars but to stay home and play America's games.

This was not always true. Before 1973 just about all healthy men had to serve in the military. There were few exceptions, and even famous athletes served their country. During World War II an estimated 5,400 of 5,800 professional baseball players (including minor leaguers) served in the U.S. military.

Thirty-five members of the Baseball Hall of Fame -- including Jackie Robinson, Joe DiMaggio and Stan Musial -- served in the armed forces during World War II, in which the United States fought from 1941 to 1945. Hank Greenberg, who led the American League in home runs in 1940, served in the military even before the Japanese attacked Pearl Harbor in 1941. Catcher Yogi Berra and pitcher Warren Spahn fought in some of the fiercest battles of the war, including D-Day and the Battle of the Bulge.

Serving in the military didn't just change players' lives, it changed their records. The great Red Sox slugger Ted Williams might have hit 700 home runs instead of just 521 if he had not missed almost five seasons while serving as a fighter pilot in World War II and the Korean War. Fireballing pitcher Bob Feller might have won 350 games instead of 266 if he hadn't fought in the 1940s.

These men were great athletes, but they were also soldiers. It is not easy to be either. Sometimes people say that a quarterback or a baseball slugger is "cool under pressure." But I wonder how many of the coolest pro players could crash-land a burning jet plane like Ted Williams did in the Korean War.

Anyone who has had the courage to fight for his or her country can be called a hero, especially on Veterans Day. Not so long ago, some of those heroes were ballplayers, too.

Fred Bowen writes KidsPost's sports opinion column and is the author of sports novels for kids.

Boston Red Sox slugger Ted Williams was a fighter pilot in World War II and the Korean War.

Pat Tillman left professional football to join the U.S. military after the Sept. 11, 2001, attacks.