Final answer:
The line 'O say can you see, by the dawn's early light' is from 'The Star-Spangled Banner', written during the War of 1812.
Step-by-step explanation:
The line 'O say can you see, by the dawn's early light' is the opening line of the American national anthem, 'The Star-Spangled Banner'. It was written during the War of 1812. The song was inspired by the British bombardment of Fort McHenry during the war, and Francis Scott Key, the author of the lyrics, witnessed the siege from a British ship.
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