Yesterday I looked in some more detail at the story Truck Convoy. What this story shows, is not only Chapman's grim pessimism about the war. It is also extremely well told. I don't know if Chapman saw or read Harvey Kurtzman's war comics. But his use of sequential panels with little more than sound effects is similar and disproves the numerous claims that this device as unique to Kurtzman and that he was the only one using it. Of course, one could try to argue that it was not Chapman doing this, the he was merely the writer. Harvey Kurtzman sketched his lay-out and his artists followed them meticuously. Hank Chapman merely worked with a typewriter.
He did this sort of tiers with Joe Maneely.
And (probably) Mort Meskin.
If you follow the link you will find more from each of these artists.