In the Gettysburg Address, President Abraham Lincoln paid tribute to those who fought and died for their cause, to which they “gave the last full measure of devotion.” Lincoln’s description of the ultimate sacrifice provides the title for Todd Robinson’s “The Last Full Measure,” which depicts the quest to award Air Force pararescue medic William Pitsenbarger the Medal of Honor 34 years after he perished in the Vietnam War.

The Medal of Honor, the military’s highest distinction, has been awarded to just over 3,500 service members who have distinguished themselves with extraordinary acts of valor in combat since the Civil War. “The Last Full Measure” is about the significance of the decoration, but as the story unfolds, it’s clear it’s as much about the journey as it is the destination.

It’s so important to his surviving Air Force buddies and the Army soldiers he rescued that Pitsenbarger receive this Medal of Honor that they spend three decades in pursuit of the distinction. By 1999, they eventually get the file on the desk of D.C. bureaucrat Scott Huffman (Sebastian Stan), who is saddled with the task of pushing through the Medal of Honor request before Pitsenbarger’s dying father (Christopher Plummer) passes away. What at first seems like an onerous task to the ambitious Huffman soon becomes a cathartic emotional exploration and bonding experience for the veterans who remain prisoners to their own painful memories of war.

The process of putting together the Medal of Honor file becomes a way to clean out the emotional wounds, as Huffman bears witness to the men reckoning with their past. At the behest of Tulley (William Hurt), Huffman sets off to interview Army vets Billy (Samuel L. Jackson), Jimmie (the late Peter Fonda), Ray (Ed Harris) and Kepper (John Savage), whom Pitsenbarger helped to save in Vietnam during the bloody Operation Abilene.

In a series of messy and chaotic flashbacks, the story of Pitsenbarger’s heroism unfolds: sent to rescue a battalion of men pinned down in the jungle by the Viet Cong, the 21-year-old Air Force medic lowered himself to the ground to treat the wounded and fight off the enemy, waving away the helicopter as it tried to pick him up, fighting alongside soldiers he didn’t know before he was killed in the night.

“The Last Full Measure” is about the healing process for the veterans and Pitsenbarger’s parents as they pursue recognition for their friend, son and hero. The star-studded cast elevates the material with nuanced performances.

What the film reveals is the deep shame and trauma vets contend with, as survivors who made it out alive, as men who are fallible and flawed who did their best under extreme violence and duress and have to live with those choices for the rest of their lives. What “The Last Full Measure” demonstrates is how powerful it can be to shed light on these experiences, through testimony, bearing witness and yes, ceremonial recognition.