I am not really sure that this poem talks about the human condition per se so much as it talks about the human condition in time of war. In this time of war, the poem is saying, the human condition is to suffer and to the best one can in such times of suffering.
This poem is a very stoical sounding poem. It is basically saying "all this bad stuff is happening to us. It is horrible and scary. But there is nothing at all that we can do about it."
If this is what the poem's speaker is saying, then the poem is telling us that human beings in war are powerless and can only suffer. They have to take what is dealt out to them and do the best they can.