The short story "The War Prayer" by Mark Twain opens with a description of a country preparing to go to war. The scene sounds similar to that you might encounter in any city, town, or village in which people believe in their flag, their country, and the righteousness of their cause. Bands play, flags fly, young men march down streets in new uniforms, and relatives and friends proudly see them off.
On Sunday morning, the new soldiers and their supporters gather in church to invoke God's blessing. A rousing song is followed by a long inspirational prayer for victory. The prayer requests that God give their country "honor and glory" and "crush the foe." Again, this is a common scene in countries preparing for war.
An old man dressed in the robe of a prophet enters the church and takes the pastor's place. He claims that he bears a message from Almighty God. He says that God will answer as long as the people who have prayed fully understand what their prayer means. He explains that the unspoken part of their prayer is that they desire to tear the enemy soldiers to shreds with shells, cause their wounded to shriek and writhe in pain, burn their homes, grieve their widows, turn their little children into starving orphans, and otherwise create great desolation and suffering. At the end of the old man's prayer, nobody takes him seriously, and everyone thinks he is crazy.
Mark Twain wrote this story in 1905, near the end of his life, as a reaction to the savagery of the Philippine-American War that resulted in the deaths of hundreds of thousands of civilians. At the time, his publisher rejected it. The story finally appeared for the first time in 1923 in an anthology called Europe and Elsewhere.
Twain was a great satirist. Here, he ridicules the religious and patriotic fervor that nations evoke as they go off to war. As they pray for victory against their foes, very few people realize the extent of the incomprehensible suffering they are asking God to inflict upon their enemies. The Old Testament of the Bible has numerous stories of prophets that confronted kings and countrymen and held them accountable for their sins.
In this story, the old man who trespasses in the church service is like one of these prophets. In God's name, he holds the people accountable for what they have wished upon their enemies. In this story, Twain is expressing the insanity of the patriotic and religious fervor that brings on such a violent spirit.