Isaac Asimov wrote an essay called The Sacred Poet in which he lists a lot of poems that have caused public opinion to rise for the subjects of those poems (or songs).
This is the poem, The Charge of the Light Brigade, set to music and sung by The Three D's.
I don't actually think much of the animation - it doesn't fit... but the song, especially toward the end, is quite emotional.
Apparently, acording to Isaac Asimov anyway, the stanzas are written in such a way as to mimic the sound of horses hooves as they charge forward.
Bqackground: During the Crimean War, a British general ordered the Light Brigade (horsemen wearing light armor, as opposed to heavy armor) to charge into a heavily fortified French post. Everyone knew it was a mistake... they had no chance to achieve their aim... nevertheless, they made the charge, and most of them died.