Army Pvt. Aaron Johnson places a small American flag in front of a grave during the annual "Flags In" event at Arlington National Cemetery in Arlington, Va. (Sgt. Jose A. Torres Jr./U.S. Army)
On Nov. 11, 1919, the first anniversary marking the end of World War I -- the supposed "war to end all wars" -- Americans began celebrating what was then called Armistice Day. It later became a national holiday, and in 1954 President Dwight D. Eisenhower signed legislation changing the name to Veterans Day to honor those who fought for the country.
Here's a brief snapshot of America's veteran population in 2016.
18.5 million: Total veteran population
That's according to the U.S. Census' American Community Survey (the figure reported by the Department of Veterans Affairs is slightly higher). The population has markedly decreased in recent years (down from nearly 22 million in 2010), with the decline in living World War II and Korean War vets. Veterans today make up nearly 8 percent of the nation's adult population.
In 2016, only three states had a million or more veterans: California (1.6 million), Texas (1.5 million) and Florida (1.4 million).
1.6 million: Female veterans
The number of female veterans has grown markedly since the Gulf Wars, when significant numbers of women began enlisting in the military and participating in combat operations.
Roughly one in five of those enlisted in the military today are black. Additionally, 6.1 percent were Hispanic; 1.6 percent were Asian; 0.7 percent were American Indian or Alaska Native; 0.2 percent were Native Hawaiian or other Pacific Islander; and 1.2 percent were some other race. 78 percent were non-Hispanic white.
In 2016, Vietnam veterans comprised the largest living group of veterans. About 5.5 million veterans served during the Gulf War era (representing service from August 1990 to present); 1.1 million served in World War II; 2.0 million served in the Korean War; and 4.4 million served in peacetime only.
In 2016, approximately 4 million veterans had a "service-connected disability," defined as disease or injury (mental or physical) incurred or aggravated during active military service. The Department of Veterans Affairs ranks the severity of a veteran's disability from 0 to 100 percent, which determines eligibility for compensation. 1.3 million veterans had a rating of 70 percent or higher.
There were nearly 40,000 (homeless veterans in 2016 (counted across the nation on a single night in January 2016). Veterans are still overrepresented among America's homeless population (about 8 percent). But the veteran homeless population has actually decreased by more than half since 2010, a result of increased local and federal efforts to provide housing and support services.
Homeless veterans tend to be male (91 percent), single (98 percent), live in a city (76 percent), and have a mental and/or physical disability (54 percent), according to the National Alliance to End Homelessness, based on the 2016 point-in-time count data.
Black veterans are substantially overrepresented among homeless veterans, comprising 39 percent of the total homeless veteran population but only 11 percent of the total veteran population.
America has never been a stranger to war. In our relatively short history as a nation, we've fought a lot of them: 11 official wars and numerous other domestic and international military conflicts that have collectively resulted in a huge number of casualties on both sides of the battlefield.
It's a sober fact we're reminded of on Veterans Day and Memorial Day, particularly in light of the nearly 7,000 U.S. troops killed, and the many more wounded, over the last decade in our most recent and ongoing conflicts in Iraq and Afghanistan.
But today, even as the U.S. military continues to grow more inclusive, Americans on average are far less likely than previous generations to either be involved in an armed military conflict or to know a friend or family member serving in one. That's in large part because the military has been an all-volunteer force since the end of the Vietnam War.
"The number of Americans who were in uniform peaked during the national mobilizations of World War I and World War II, particularly the latter, when more than 16 million Americans were in the armed forces. As a proportion of the population, 14 times as many Americans served in World War II as did in the wars of the last decade."
Also stark, notes Waldman, is the rate of U.S. fatalities rates in today's conflicts as compared to those of even the recent past: "In Vietnam, the figure was one death for every 58 who deployed, and in both World War I and World War II it was around one in 40. During the Civil War it was one in five. That of course meant that many more Americans would know someone who died."
In short, modern American warfare has become less a national sacrifice than it once was, with a significantly smaller percentage of the nation's population bearing the burden.
Keep in mind that some of these figures, particularly those from older conflicts, are rough estimates. Sources are listed beneath the chart.