One dominant theme in Louise Erdrich's short story "The Red Convertible" is the clash between Native American and Western warfare values. Erdrich depicts Native Americans as warriors, which is clearly seen in his reference to Red Tomahawak, a Yanktonai of Dakota known for shooting the Sioux tribal chief Sitting Bull for resisting arrest and rebelling against the US government. It is due to the Native American drive to be warriors that Henry decides to enlist in the Vietnam War.
However, when Henry is captured as a prisoner of war and witnesses all of the horrors associated with the war, he sees that war is anything but glorious. Not only was the Western war in Vietnam bloody and gruesome, it proved to be a pointless, unsuccessful loss of life, which clashed with Henry's warrior instincts. As a result, Henry feels unfulfilled, and his post-traumatic stress disorder is made worse by his feelings of having failed as a warrior. Erdrich depicts the toll the war took on Henry in passages like the following:
When he came home, though, Henry was different, and I'll say this: the change was no good. ... But he was quiet, so quiet, and never comfortable sitting still anywhere but always up and moving around.
In showing his readers the toll the war took on Henry, Erdrich is showing that, when it comes to warfare, Native Americans and Westerners have different values. Westerners only value making a mark through any means at their disposal, whether those means are moral or not, whereas Native Americans value fighting for a just cause, fighting honorably, and fighting as warriors. Fighting warfare in ways that contradicted his values oppressed Henry so much that he felt compelled to take his own life.