The blessings of war are few, but one hard- won result of the nation’s conflicts is expertise in accounting for the dead. The Revolutionary War, the War of 1812 and the Mexican War together claimed some 58,000 lives, on and off the battlefield. But lax records and hasty on-site burials meant the number of unknown fatalities from those formative American wars remains a mystery.

Record-keeping improved with the Civil War, still the nation’s deadliest conflict. But because the conflict involved millions of men, shifting fronts and hurried burials, the percentage of soldiers who went to their graves without names is astounding. One in four were never identified.

Determined to do better, the United States fielded specialty teams to recover and identify its fallen soldiers and sailors from the Spanish-American War, bringing thousands home from Cuba, Puerto Rico and the Philippines for burial. As a result, the percentage of unknowns plummeted. The number of total American deaths from World War I, the first conflict of truly global proportions, shocked the nation: 116,000 deaths in about 18 months of fighting.

In 1921, the unidentified remains of one of those soldiers became the first body interred at Arlington National Cemetery’s Tomb of the Unknown Soldier.

Nevertheless, because of advances in battlefield recovery, better records and the introduction of dog tags, the number of unknowns in our first great war dropped markedly, to about 2 percent, a rate that held through World War II and the Korean conflict.

Thanks to refinements in forensic dentistry and the use of X-rays and CAT scans, the number of unknowns has continued to dwindle with each subsequent war. In 1998, Arlington’s unknown service member from the Vietnam War, who was buried in May 1984, was disinterred and identified as First Lt. Michael J. Blassie, an airman shot down in 1972. With elaborate honors, he was returned to his hometown, St. Louis. His tomb at Arlington remains empty, marking the first 20th century conflict for which there is no unknown warrior.

In the three major wars since — the Persian Gulf war and the conflicts in Iraq and Afghanistan — there has not been a single unknown soldier, and only one combatant has been listed as missing in action: Capt. Michael Speicher, who was shot down over Iraq in 1991. His remains were recovered from the Iraqi desert in August 2009 and returned to his family.

The sad reality is that there will likely be new recruits for Arlington’s ranks, now 300,000 strong. Though all losses are painful, perhaps we can take some consolation in the knowledge that the names of those who will sacrifice so much are unlikely to go unknown.

Robert M. Poole is the author of “On Hallowed Ground: The Story of Arlington National Cemetery.” Rumors is a design studio.