It has been a hundred years since humanity spun into the chaos of the First World War. Peter Jackson’s acclaimed new documentary, “They Shall Not Grow Old,” brings vivid new life to the experience of British soldiers fighting on the western front. Using newly released footage from the Imperial War Museum, Jackson and his team worked four years to digitally restore, smooth, colorize and convert the film into 3D. The narration is told completely by former soldiers, in their own voices, from interviews recorded by the BBC in the 1960s and 1970s.

WWI is a case study of human evolution. Britain entered the war as a traditional culture (amber altitude), full of romantic visions of honor, duty and the glories of war. Young men, thrilled by the promise of adventure, clamored to answer the call.

Once at the front, they soon realized that they were in a meat-grinder, beset not only by age-old battle curses like hunger, cold, mud, sickness, rats and lice, but also the emergent features of modern weaponry: aerial bombs, poison gas, machine guns, flame-throwers and tanks. Yet the men endured, no longer sustained by romance or politics, but like warriors of all time, by the dense connection created between men whose next breaths depend on each other (red altitude).

Those who survived returned to a country that in the meantime had largely modernized both in structure and thought (orange altitude), a country more interested in looking forward than past. The soldiers found themselves out of work, invisible and misunderstood by all but their fellow fighters.

Jackson leaves it there, but the developmental story continues, with a new postmodern view (green altitude) arising in Germany out of the rubble of defeat. This is exemplified by the classic war novel All Quiet on the Western Front. Also told from the point of view of the soldier – this time a German soldier – it is a scathing condemnation of a civilization that could create such suffering. The book was an immediate international sensation, translated into 22 languages, and brought a potent blast of green consciousness to the world (and into my life fifty years later). But alas, it was soon to be banned by the Nazis … humanity had more of the lesson to learn, and still has.