The War Prayer by Mark Twain (1916) at the seminary library book sale this past year -- it just called out to me from in between all the theological tomes and philosophy books.
Twain wrote this poetic protest in response to the Spanish-American war but wouldn't let it be published during his lifetime out of respect for his family, who thought the sentiments too harsh. It was first published in Harper's in 1916, in the heart of World War I, and has been a perennial favorite whenever the nation goes to war.
The copy I have was published during Vietnam, in 1971. Here Twain's words are accompanied by the powerful and chaotic line drawings of John Groth. The combination of the words and images really help to twist Twain's knife. Definitely worth a read.
[And if you want to read it (without Groth's wonderful illustrations) it is all right here.]