There exists a phrase or device, somewhat akin to the parables of Paul Bunyan or John Henry, when your efforts at protest are futile against a struggle, but you are compelled to struggle against it anyways -- usually because it's a seemingly noble cause.
Would anyone have a suggestion as to how to phrase this device? Or is there a widely known idiom for it? I'd suppose the single word "futile" might accurately describe this situation, but that's not what I'm looking for.