The speaker begins by rejecting falseness: smiles that offer no comfort and a surface they can no longer trust. From there the poem slips into a memory, or perhaps an image, of swimming in a lake on the last day of a "rebellion." Lies arrive, and the swimmers' bodies begin to drown. They even despise their own lungs, as if the air they are given were counterfeit, a "real nothingness."
The middle question is the bleakest. If "they" had won, why would we have shot our own sons and daughters? The poem seems to suggest that conflict, whatever its cause, ends up hurting those closest to us, though the exact event stays unclear. The speaker then wonders whether wounds have healed and whether shallow people will ever grasp what broken bones mean.
The mood is weary, bitter and quietly defiant. The closing lines shrug at the lack of answers and point to a "human parade" that leaves people blind, a final note of resignation.