i say execution is acceptable by groups in precarious situations (i.e. not well-established states with legal systems and cops, but we'll come back to that) such as during or shortly after a revolution where you can't securely contain and rehabilitate the monsters who have been abusing peasants or slaves, and there's a real risk of them leaving and mustering an army or otherwise undermining the revolution.

we blanketly oppose the death penalty in for a variety of reasons that have to do with systemic injustices but none of those problems apply to viet nam or billionaires.