More than 43 million Americans have served or are currently serving their country — and more than 1.3 million gave the ultimate sacrifice.

According to the U.S. Census Bureau, there are approximately 15.8 million U.S. veterans living today — about 6.1 percent of the adult population. Roughly half are age 65 or older and nearly 2 million are under 35.

Our older veterans served in World War II, Korea, and Vietnam. The younger veterans primarily served in Iraq and Afghanistan after the 9/11 attacks.

World War II veterans are dying at a rapid pace. According to the U.S. Department of Veterans Affairs, fewer than 100,000 are still living, down from 16 million who served.

Of the 5.7 million Americans who served in the Korean War, approximately 767,000 are still alive. My father, who served during the Korean War, left us nearly three years ago at the age of 89.

As for Vietnam, around 5.6 million of the 8.7 million Americans who served in that war are still living.

To round out the numbers, more than 8.4 million veterans have served during the Gulf War era, which spans from 1990 to the present. Additionally, approximately 4.4 million served during peacetime.

Some living veterans served across multiple war periods. Nearly 63,000 served during the Vietnam War and both Gulf War eras — from August 1990 through August 2001 and again from September 2001 onward.

More impressively, nearly 37,000 living veterans served in World War II, the Korean War, and the Vietnam War.

Many Americans confuse Memorial Day with Veterans Day. While Veterans Day honors all who have served — living or dead — Memorial Day is specifically for those who died in service.

It began after the Civil War as “Decoration Day,” a time to decorate the graves of fallen soldiers. Today, it’s a day of national mourning, and rightly so.

To date, more than 1.3 million Americans have died in military service. About 4,500 died during the American Revolution. In the Civil War, around 370,000 Union soldiers and an estimated 260,000 Confederate soldiers lost their lives.

We lost 116,516 in World War I and nearly 405,000 in World War II. The Korean War claimed 36,574 lives; the Vietnam War, 58,220.

Modern warfare has led to fewer battlefield deaths — a silver lining of improved medical care and technology.

Of the Americans who served in Iraq and Afghanistan, more than 7,000 died.

 Nearly 50,000 were wounded and many still suffering from their injuries.

Many of today’s veterans face challenges well beyond the battlefield. Many struggle with PTSD, physical injuries, job placement and endless health challenges.

In any event, each veteran who gave the ultimate sacrifice represents a life cut short — young men and women who never came home, never started a family, never got to see the freedoms they died to protect.

Their families carry that loss forever. Their sacrifice is not just national — it’s heartbreakingly personal.

Yes, the purpose of Memorial Day is to honor the men and women who gave the ultimate sacrifice for their country.

While we kick off this summer, let’s take some time to remember, thank and honor them for their service.

While we do so, let’s also pay homage to all of the many men and women who have served, or are serving, our country.

Tom Purcell is a Pittsburgh Tribune-Review humor columnist and is syndicated by Cagle Cartoons. Email Tom at Purcell@caglecartoons.com.