The aspect of this poem that most clearly marks it as a work of Modernism is "It focuses on a single subject - the atrocities of war."
Explanation:
The poem "Grass" by Carl Sandburg is considered a modern poem, since it follows many of the lineaments of that style, it is free verse and it uses imagery as a recurrent literary device, in this line in specific it give the imagery of the grass growing as a way to cover the horrors of war, modern poem also focus in human conscience and war is presented from the conscience of the writer.
