Themes:
* War: The novel centers on the American Revolutionary War.
* Family: The story explores the complex dynamics of a family torn apart by the war.
* Loss: The loss of innocence, the loss of a brother, the loss of a way of life.
* Loyalty: The protagonist grapples with loyalty to family and to his own beliefs.
* Coming-of-age: The novel chronicles the protagonist's journey from childhood to young adulthood.
Tone:
* Tragic: The events of the war and the loss of Sam leave a deep sense of tragedy.
* Poignant: The story evokes strong emotions and empathy for the characters.
* Realistic: The novel provides a grounded and unflinching look at the realities of war.
* Intimate: The story is told from a personal and intimate perspective.
Other:
* Historical: The novel is set during a specific historical period.
* Powerful: The themes and the narrative have a strong impact on the reader.
* Thought-provoking: The novel raises questions about war, family, and loyalty.
Ultimately, the best single word to describe *My Brother Sam is Dead* depends on your interpretation and the specific aspect you want to emphasize.