I think possibly the most just and powerful punishment would be to make the false claimants present themselves in front of the national memorial, to stand up and declare that their claims are fraudulent and shameful on prime time national television and then apologize to the nations war dead for their deception.

I imagine that after a few of those, that a dumb shmuck who wants to puff himself up by pretending to be a war hero might think twice about how much glory there might be waiting for him.