The rhythm of "Beat! Beat! Drums!" already gives us a feeling of order and structure. Heck, even the title sounds orderly! But the speaker of this poem provides this sense of order just to have it blow up in our faces. During peacetime, people go to certain places at certain times: there are church meetings and court cases, classes and business deals. But the war won't let any of that continue: through the music of the bugles and drums, the war does its best to disrupt the routines and order of American life.
Our speaker wants all the normal social routines to be broken because he believes the war should be everyone's first concern.
The suggestion that even the dead are shaken by the music of war tells us that there is no normal rule or order that is free from the war's effects.