On Sunday, PBS will start screening “The War,” the latest effort from America’s master of the film documentary Ken Burns. On Monday evening, at MoMA, the film was given its premiere at which a wide selection of scenes from the 14-hour series was screened.

At the end of the show, the audience roundly applauded, but there was little of the buzz and excitement to be found at a traditional film opening. We had all just observed some of the most harrowing scenes ever caught on camera, and were left somewhat stunned by what we had witnessed.

At the party afterwards, everyone I spoke to found something else to talk about; the death and destruction we had just witnessed, the memories of the veterans which 60 years on still choked them with tears at the telling, the haunting images of the Nazi death camps and the genetic experiment hospitals, and the Japanese banzai charges and civilian mass suicides were simply too strong to become the stuff of idle chitchat.

As in his masterwork “The Civil War,” Ken Burns foregoes the broad political sweep of history in favor of intimate stories told by ordinary Americans. This miniaturist approach helps us understand today what going to the war meant to our parents, grandparents, and great-grandparents. They took part unstintingly and uncomplainingly in a mission they believed was worthwhile and we all owe them more than we can express.

But watching this extraordinary exercise in intelligent television begs the question, what lessons can we learn from “The War” that we can apply to our understanding of the Iraq War?

The main thing, perhaps, is that when we talk of war we are talking about myriad human dramas, not a glib geopolitical debating exercise among Internet generals. Wherever our troops fight, they remain brave individuals trying to do a good job on behalf of all of us as best as they are able. When they face the prospect of death or maiming each day, they do not deserve to be sniped at from the folks back home.

Wars are also something the whole country shares. The Iraq War is no more “Bush’s War” than World War Two was “Roosevelt’s War.” Although Hitler had reached Paris having swallowed Austria, Poland, Czechoslovakia, Denmark, Norway, Holland, and Belgium, Roosevelt still fought the 1940 election on a promise not to send American boys to war. But when he declared war against the Axis powers after the Japanese attack on Pearl Harbor, the nation rallied around him.

It is in the nature of a democracy that when a country is at war it becomes the whole nation’s responsibility to win it. In World War Two, those who objected to the aims of the war, or refused to play their part, were considered traitors to America and treacherous to their friends and neighbors. It was possible to hold private reservations about the war or the way in which it was being directed, but it would have been unconscionable to have undermined the war effort or threatened the withdrawal of funds for our fighting forces.

Things go wrong in war, but it serves no purpose to harp on the mistakes. It would take a long list to enumerate the many errors on the Allied side during World War Two: the Allied invasion of Norway, the Allied landings at Dieppe, the Allied parachute drop at Arnhem, the roll goes on and on. But the biggest error of all was to delay confronting the dictators. It is far easier to preempt a danger than allow it to fester.

As Winston Churchill told Congress in December 1941: “Five or six years ago it would have been easy, without shedding a drop of blood, for the United States and Great Britain to have insisted on fulfillment of the disarmament clauses of the treaties which Germany signed after the Great War.” As he put it, “If we had kept together after the last war, if we had taken common measures for our safety, this renewal of the curse need never have fallen upon us.”

As Ken Burns’s film reminds us, six million Jews were murdered by the Nazis, as well as two million non-Jewish Poles, and four million Russian prisoners of war, not to mention millions of homosexuals, gypsies, mentally and physically handicapped, and political opponents of the Nazis. The loss of life on all sides during World War Two totaled a horrific 72 million, divided between 61 million Allied and 11 million Axis lives. How many might have been saved if there had been no isolationists, apologists, or appeasers to delay America’s entry into the war?

Then there is the question of political leadership. Whatever Americans may feel about the peacetime policies of Franklin Roosevelt and Winston Churchill, few doubt their inspirational qualities when it came to rallying their people behind the war and maintaining morale under trying circumstances.

We continue to live in a world riven with danger. Wild men make ugly noises threatening their neighbors with annihilation. Attempts to ensure the peaceful disarmament of those who terrorize and bully are often as half hearted and ineffective as they were in the Thirties.

When it comes to picking our next commander in chief, it is worth considering who would be best in a crisis, who has the confidence and commitment to do what is necessary, come what may, and who has the perspicacity to recognize danger when it is on the horizon, not when it has already reached our shores or those of our friends and allies.