How does the "Star-Spangled Banner" elicit feelings of love and pride for one's country through both its words and instrumental pieces?

The context of the "Star-Spangled Banner" is that it was written by Francis Scott Key during the War of 1812 about the British bombardment of Fort McHenry during the Battle of Baltimore. The American flag that remained during the battle, which ended in an American victory, inspired Key to write a poem called "Defence of Fort M'Henry." Though the poem is four stanzas in length, only the first stanza was used for the song.
The lyrics of the song celebrate the American flag, which was not really a symbol of the country until the War of 1812. That war, considered the second war of American independence, made the United States definitively free from British rule. The lyrics present vivid imagery, including the "dawn's early light." Even then, the "broad stripes and bright stars" remain visible. The flag is a symbol of American permanence and strength in the wake of attack. As the flag survives the battle, so too will the United States survive. The lyrics use a great deal of alliteration—the repetition of initial sounds—such as "the rocket's red glare," enhancing their poetic quality. 
The music was set to the tune of "The Anacreontic Song" by English composer John Stafford Smith. As the range of the music is one octave and one fifth, it is considered a difficult song to sing. It requires vocal training to hit all the notes. The instrumental version, often played by military bands, is often considered very rousing. In 1917, John Philips Sousa and others made an official arrangement for the army and navy. This version was harmonized by Walter Damrosch and arranged by Sousa, making it exciting and expertly arranged.
https://amhistory.si.edu/starspangledbanner/symbols-of-a-new-nation.aspx