The poem "Flag" by John Agard explores the power of national flags to influence human behavior and emotions. Through a series of rhetorical questions, the speaker suggests that a flag is just a piece of cloth but has the power to stir strong emotions in people and compel them to acts of bravery, aggression, and self-sacrifice. The last stanza implies that embracing blind patriotism can justify ignoring one's conscience. Overall, the poem presents a skeptical view of nationalism and questions whether flags have inherent power or if that power is granted by people.