A poorly executed conspiracy is still a conspiracy.

The word ‘conspiracy’ itself has a legal, original, meaning entirely different from the popular meaning. I find all good discussions involving this clarify what meaning is intended.

I resort to just saying the definition of words, in a sentence, instead of the word itself.

I've told and convinced plenty of anti-vaxxers about the magical secret way our body naturally produces antibodies if we expose our body to dead versions of a virus (or, now, things shaped like that virus). They like magic, secrets and nature, they do not like the word vaccine.

I do the same with the word conspiracy, "That is a secret plan by a group to do something harmful". It rolls off the tongue.

The only really effective way to change someone's mind is to make them believe they came up with the conclusions themselves

No, it was simply a lie. And one that should have fallen completely flat. My respect for Colin Powell went through the floor that day.