The speaker describes being conscripted, and the picture is bleak. Going to war, he says, means gathering with the others and keeping quiet, trading ordinary cheer for something like a prison cell. The poem never shows a battlefield. It stays with the dread of the lead-up, when a person's own will no longer counts for much.
The speaker's response is to stay drunk, and he calls himself "a thing for finishing," as if he's already an object waiting to be used up. That phrase makes him sound less like a person and more like something on a list to be dealt with. The last line, in parentheses, is hard to pin down. "No hope is to go" could mean that going offers no hope, or that the only hope left is not going. Either way, it reads like a quiet aside, almost muttered.
The mood is numb, resigned, and tightly compressed. The short lines leave little room for protest.