I don't know if there's a term for this kind of subtle smear phrase, but this drives me crazy. It's in the same class as "when did you stop beating your wife?"
Lesser evil does not mean evil. Cuddling puppies is less evil when compared to murder. But would you say cuddling puppies is evil? The only way you'd be saying cuddling puppies is evil would be in the context of some puppy hater saying cuddling puppies is the lesser evil compared to murder.
