What ideas does the poem "Eighth Air Force" by Randall Jarrell emphasize?

Randall Jarrell’s “Eighth Air Force” meditates on various themes relevant to warfare. The speaker, an airman himself, observes the environment and conduct of other airmen in a military hut. Lines 2-4 describe how

A puppy laps the water from a can

Of flowers, and the drunk sergeant shaving

Whistles O Paradiso!

The puppy's innocent playfulness contrasts with the warfare already suggested by the poem’s title, especially the devastating industrial warfare symbolized by modern airpower. Likewise, the presence of the flowers suggests that although airmen kill, they can nevertheless appreciate beauty. Meanwhile, the drunk, whistling sergeant symbolizes the pleasures of innocent, ordinary life, although his present job compels him to behave in ways that are largely and inevitably destructive. The fact that he whistles an opera aria concerning paradise is doubly ironic: he is a somewhat cultured man whose job is to kill or be killed, and he sings about paradise in a situation that is anything but perfect and beautiful.

At the end of the first stanza, the speaker raises crucial questions: do these kinds of innocent behaviors, motives, and personalities contradict the common notion that man is “a wolf to man?” (5). Do moments of tranquility and beauty and humanity during war really change the fact that war is ugly and brutal or absolve soldiers of guilt for killing?

The second stanza develops the basic idea implied in the first: that the airmen who are in some sense “murderers” are also, in their regular lives, normal human beings who behave like most people: they feel tired, play games, sleep, reflect on the past, play with puppies, and have hopes for the future (the airman counting his missions is hoping to being sent home after he completes one last assignment). Yet they are also trained, highly skilled killers who themselves face the real prospect of death.

The same men who kill (by engaging enemy fighters, by bombing military targets, and perhaps even by bombing cities) are as youthful, playful, vigorous, and lively as the puppy whose company and antics they enjoy.  The speaker admits that he himself has also participated in modern warfare but has been lucky enough (so far) to survive (12-13).

In the next lines, however, the speaker begins to allude to the treatment of Jesus by Pontius Pilate. Pilate presented Jesus to a crowd determined to condemn him and said "Behold the man” – a phrase Jarrell echoes in line 15.  The speaker's conscience is apparently troubled: he realizes that in some senses his military duties are incompatible with his Christianity (16-17).  He realizes, too, that his comrades are also killers, but he can't in good concience openly or unequivocally condemn them.  He resists any impulse to metaphorically crucify the men who fight wars, just as Pilate initially resisted the crowd who wanted Jesus crucified (John 19). Pilate soon relented, however, and allowed Christ's crucifixion, even though he explicitly announced, “I find no fault in him” (John 19:6). The poem's last line alludes to Matthew 27:19, where Pilate’s wife warned her husband, “Have nothing to do with that just man: for I have suffered many things this day in a dream because of him.” Just as Pilate found himself in a highly troubling situation, so does the speaker of this poem.