The worst monsters among us have one particularly insidious weapon that they use all the friggin time, but most people rarely spot it. They'll say something that knocks you down or makes them look good or otherwise pushes their agenda, and it'll seem SO true that you almost can't help but agree with it. And 90% of it will indeed be completely true. That's the problem - the 90% that's true makes the subtle little twist in the other 10% a million times more believable. And yet, that subtle twist changes everything. It makes a lie out of the whole thing, and creates a subtle dementation of your view of reality. Lies can be shrugged off - but lies that seem utterly like truth? They distort everything, because they get past your defenses and stick with you. You can feel it when it happens, like an old instinct to spot predators, but rarely do any of us truly recognize that that danger-sense is activating because of the person right in front of us. They seem so normal and likable, right?
The worst weapon of evil people isn't the lies that they breathe out like air - it's the truth that they wrap around those lies, to make them believable.