tilt at windmills
idiomPart oftilt
tilt at windmills — idiom
1. to waste your energy fighting opponents or problems that are not real or cannot
1.idiom
Definition
to waste your energy fighting opponents or problems that are not real or cannot be defeated (from the novel Don Quixote, in which the hero attacks windmills, thinking they are giants)
Example
Christopher worried that his campaign against the big company was just tilting at windmills.
Instead of tilting at windmills, the activist focused on smaller, winnable local issues.