Lyric discussion by Communism57 

Cover art for Mrs. McGrath lyrics by Bruce Springsteen

Why hasn't anyone commented? So this song's about how this Irish guy, Ted McGrath, joins the British Army, and gets sent down to Iberia to fight Napoleon in the Peninsular War. While in Portugal, he loses his legs to a cannon ball, probably in either the Battle of Barrosa, or the Battle of Fuentes de Onoro (Both having taken place on and around May 5. The song ends with with a statement which can be applied to America's current situation in Iraq, and Springsteen probably chose the song for exactly that reason.

"All foreign wars I do proclaim Live on the blood and the mother's pain I'd rather have my son as he used to be Than the King of America and his whole navy"

Hope I helped.