Survival
The film depicts a moment in World War II where active battle was not the aim, but rather the evacuation of the beaches of Dunkirk. Pushed onto the beaches by German troops, the French and British soldiers found themselves without a way of getting back to their homeland, in spite of it being within view across the English Channel. As the Germans continue to fight and bomb the English, soldiers must work together to find alternative solutions as the hope of evacuation becomes dimmer and dimmer. The film takes a close look at the fight for survival, the lengths to which people go to survive and the sacrifices they make in order to help others. Christopher Nolan even acknowledged that the film is not a standard war film, but a film about survival above everything else.
Nationalism
Another theme in the film is the idea of national pride. During the siege of Dunkirk, the British government made efforts to evacuate the British troops stranded at Dunkirk, as they wanted their troops back home in order to prepare for a possible attack on England. They had no intention of evacuating the French soldiers in Dunkirk, even though French soldiers were fighting alongside the English. For the British government, the British soldiers were the ones that mattered, and the rest were just collateral damage for them. However, there were still people in the British army who considered the French valuable and did what they could to save them. This tension between nationalism and the desire to help other human beings more generally is explored through the prejudice that Alex feels towards Gibson and Tommy's defense of Gibson. While Alex feels that the fact that Gibson is French—a "frog" as he calls him—makes him less trustworthy, Tommy insists that he is an ally who is worthy of help. This theme is also depicted in the character of Captain Bolton, who stays behind even after hundreds of thousands of British soldiers have made it back to England, because he wants to help the French soldiers who are still there.
Every bit of help counts
When the commanders at Dunkirk are informed that the British government does not plan to send any destroyers or big ships to evacuate them, they became discouraged. It seems that they will die stranded on the beach. Soon enough, they find out that civilian boats are being requisitioned, but that promises little hope as they believe that there will not be enough boats to provide adequate support. Ultimately, the civilian boats are what save the day, as hundreds of boats appear on the horizon and help the soldiers get home. While Churchill had estimated their evacuation goal as 40,000, with the help of the civilian boats, the army manages to get over 300,000 troops home. The film explores the ways that small acts of service and help from ordinary people can make the difference in moments of crisis.
Sacrifice
A related major theme in the film is sacrifice and the risks that soldiers must take for the greater good. The character who perhaps best represents this theme is the fighter pilot Farrier, who goes above and beyond the call of duty to fight for his country. Even after he has the option to return to England and remain safe from the vagaries of war, he opts to continue flying and shooting down German fighters that are trying to sabotage the evacuation. He flies until he runs out of fuel, and even after he has, he shoots down more planes, before landing on a beach and getting captured by German soldiers. Farrier typifies the self-sacrificing attitude that many of the soldiers take in order to help the larger cause and ensure the safety of their fellow Englishmen.
Fear
Tommy, Alex, and Gibson are younger soldiers who are looking to get off the beaches at Dunkirk by whatever means possible. They are brave in many ways, but they are also depicted asmore selfish thank many others, with Tommy and Gibson masquerading as medics to get on a destroyer and Alex becoming belligerent towards Gibson in a moment of tension on the beached trawler. They spend a great deal of time grappling with their own fear, and it is this fear that leads them to behave impulsively, and to act desperately in their fight for survival. In many ways, they contrast with a character like Farrier, who sacrifices himself for the greater good. His sacrifice is connected to a deep bravery, whereas they are less interested in sacrifice than they are in survival, motivated by their fear of death.
Honor
While desperate times call for desperate measures, many of the characters in the film are motivated by their desire to act with honor and nobility. Bolton and Winnant both want to be honorable and brave in the way that they handle the evacuation of the beaches, in spite of their own fears about its impossibility. Another character who is committed to a sense of honor is Mr. Dawson, a man who takes his son and his son's friend to collect soldiers with his own boat. He believes that it is honorable to pitch in and help, even—especially—in dark times, when this means danger or sacrifice. George, Peter's friend, is also motivated by his desire to live honorably, in spite of his being a rather unimpressive figure in his own life. When George dies tragically on Moonstone, Peter makes sure he is remembered in honorable terms, and goes to the local newspaper to report that he was one of the heroes of the Dunkirk evacuation, a fact which is reflected in a headline the following day.
War is hell
For all the heroism that takes place in the film, Dunkirk portrays war as brutal, violent, and horrific. As we follow the perspectives of the British soldiers trapped on the beach, we feel the suspense of their not knowing whether they will return home alive, and their fear of the next torpedo or bomb that might get used against them. Dunkirk is a beautifully shot and epic film, but it does not romanticize war. In focusing on an isolated evacuation and the terror of that incident, the film shows that war is, indeed, hell.
