One of the most compelling features of Jarrell's poem is the way he truncates the ball-turret gunner's life, literally and figuratively encapsulating his life into the plexiglass ball of his turret:
From my mother's sleep I feel into the State/And I hunched in its belly till my wet fur froze./Six miles from earth, loosed from its dreams of life. . . .
It is as if the ball-turret gunner--it's important to note that he has no identity except as a ball-turret gunner--has no life before, and certainly no life after, his brief life in the ball turret. Instead of humanizing the man, the person--most likely a teenager or in his early 20s-- Jarrell describes him in terms of what he wears as a gunner, which also makes the gunner less than human in a sense. His "wet fur" describes his heavy alpaca-wool-lined flight suit, soak in his sweat because of the fear he faces. Clearly, the ball-turret gunner, at least according to Jarrell, has no meaningful life before he becomes a part of the "State," the machine that eventually precipitates his death.
Not only did he have no life before he "fell into the State," the gunner, because his meaningful existence is defined as a ball-turret gunner, no longer has even dreams of a normal life. His entire universe is encompassed by a few square feet of plexiglass, and his existence depends on elements totally beyond his control--he no longer even dreams of normal life because it has no relevance to his circumstances.
The last two lines depict the gunner's complete detachment from life:
I woke to black flak and the nightmare fighters./When I died they washed me out of the turret with a hose.
Essentially, the gunner was born, dropped into the turret of an American bomber, and his first real memory is of the enemy fighters and flak that eventually kill him. Because he is able to report the facts of his death in such a matter-of-fact manner, his detachment from this horrific end is complete. While he was a ball-turret gunner, he was part of a machine (a bomber and, in a larger sense, the State), and he reports his own death as if he were reporting damage to machinery--no sadness, no regret, just a final report.
I think it's polemical in that Jarrell makes the case that war dehumanizes those who are asked to fight--which is why the gunner falls directly from his mother's womb into the State (in this case, the Army Air Force) and had no chance of a real life. Because Jarrell himself was in the Army Air Corps during WWII and undoubtedly saw the necessity for our participation in the war, I doubt that the poem has a political element, but it certainly makes a statement about the nature of war.
Thanks that helped a lot :) Do you happen to know how the poem is political and polemical? If not it's okay...Thanks so much!