In a stunning display of callousness, the Defense Department has announced that thousands of soldiers — many serving as commanding officers in Afghanistan — will be notified in the coming weeks that their service to the country is no longer needed.

Last week, more than 1,100 Army captains — the men and women who know best how to fight this enemy because they have experienced multiple deployments — were told they’ll be retired from the Army.

The overall news is not unexpected. The Army has ended its major operations in Iraq and is winding down in Afghanistan. Budget cuts are projected to shrink the Army from its current 520,000 troops to 440,000, the smallest size since before World War II.

What is astonishing is that the Defense Department thought it would be appropriate to notify deployed soldiers — men and women risking their lives daily in combat zones — that they’ll be laid off after their current deployment.

As one Army wife posted on MilitaryFamily.org, “On some level I knew the drawdowns were inevitable, but I guess I never expected to be simultaneously worried about a deployment to Afghanistan and a pink slip because my husband’s service is no longer needed.”

Yet the issues go far beyond thanklessness. The nation should worry about the increased national-security risk of separating such a large pool of combat-experienced leaders. The separated soldiers are those who carry the deepest knowledge base of counterinsurgency operations.

A senior Defense Department official warned: “If the force is smaller, there’s less margin for error. Let’s face it — things are pretty uncertain out there.”

Commenting on the extraordinarily large number of captains being retired, Army Vice Chief of Staff Gen. John Campbell said: “In other times, they’d probably continue to stay in the Army. But these are not normal times.”

Indeed not. While mass layoffs in the private sector generate front-page headlines, the media have largely ignored the reduction of our military. But who can blame them?

The war-weary public doesn’t want to hear that the cuts put the country at risk.

After more than a decade of fighting, even the most faithful — who used to rally behind the troops in Iraq and Afghanistan by sending CARE packages filled with cookies, candies and reminders of home — have moved on with their lives, with few thoughts of the soldiers still serving there.

And for far too many, a soldier is an uncomfortable reminder of what we have failed to do in the Middle East.

The most famous soldier in the country at the moment is not Lance Cpl. Kyle Carpenter, who was recently awarded the Medal of Honor for absorbing the brunt of a grenade blast in order to save a fellow Marine.

Instead, the media has focused on Sgt. Bowe Bergdahl, a soldier who appears to have deserted his unit.

Consumed with the Bergdahl trade, most have ignored the death of Capt. Jason Jones, a heroic Special Forces commander killed by the Taliban in a firefight in Afghanistan less than a week after the Bergdahl release.

Capt. Jones was mourned by his family and his friends. He will never be forgotten by the soldiers who served with him and the cadets he led in his years at West Point.

The US Military Academy has paid a high price for these post-9/11 wars.

According to the Naval History and Heritage Command, the West Point cadet-to-death ratio in Iraq and Afghanistan is 11 times higher than the ratio experienced for the Academy in World War II, four times greater than during the Korean War and more than three times greater than in the Vietnam and Persian Gulf wars.

None of our soldiers has ever asked for our gratitude — they never really expected it. But they did expect to be able to finish the job they trained to do.

Sending pink slips to commanders still serving in a combat zone is wrong. They deserve so much better than this.

Former US Army Capt. Jon­athan Hendershott (West Point, 2007) served in Iraq with the 101st Airborne Division and as a company commander in Ft. Hood, Texas. He lives in New York City.