What is the straw man fallacy?

Distorting someone's position into a weaker, exaggerated caricature, knocking that down, and claiming you've refuted the real position.

The pattern: A holds position X; B substitutes a distorted version Y that's easier to attack; B attacks Y; B concludes X is defeated. It fails because demolishing a misrepresentation leaves the real position untouched — "one might as well expect an attack on a poor drawing of a person to hurt the person."

A: "We should reduce the defence budget slightly." B: "So you want to leave the country completely defenceless against invasion? That's reckless."

A never argued for zero defence; B invented an extreme version ("completely defenceless") because it's easy to ridicule. The honest move is to engage the actual, weaker claim.

Tip: The opposite virtue is steelmanning — restating your opponent's view in its strongest form before responding. If your summary of their position would make them say "that's not what I said," you may be building a straw man.