There are 1.4 million Americans presently in uniform, according to the Department of Defense. While most are serving at home, many have likely served in Iraq and Afghanistan, home to most of the last decade's battlefields.Troop levels in Iraq approached 150,000 during the height of that war, and deployment in Afghanistan is presently about 100,000. Though the war in Iraq is over and there's hope our troops will soon be out of Afghanistan, thousands of Americans still serve in other global hot spots, such as South Korea, where 25,000 Americans are assisting our ally.But that's just part of the picture. Those who have served our nation have a long, proud history.According to the U.S. Census Bureau, of the 311 million people in the United States, about 21.8 million are veterans. That's about one in 14 people you'll meet on the street, a fairly large percentage of the population. But a "typical" veteran is hard to define. For example, Census Bureau figures show the odds of meeting a World War II veteran are about one in 150. Korean War veterans number about one in 120.About one in 40 people served during the Vietnam War era, and about one in 57 living Americans have served our country during peace time.The youngest veterans have served since the Gulf War in 1990. They comprise about one in 65 of all Americans.Civilians can never fully understand what it's like to be a veteran. Some volunteered and some were drafted. They all left family, friends and home for remote military bases and jobs full of hard work and long hours. Many have faced extreme and dangerous conditions, and mind-numbing boredom. Many have confronted people of other cultures in harsh, uncaring lands, accomplishing life-changing and life-saving missions. Many have fought, been wounded and watched their comrades die.Whatever their service, in whatever era or capacity, all have done more than their part to make this the great nation we have become. They deserve our lasting gratitude, on this Veterans Day, and every day.