Never mind Keynes; Milton Friedman had crusaded against this kind of thinking.
But it was Carter who first crusaded for the U.S. to wean itself off of its dependence on oil.
The Texas crusader let it slip this week that she is badly misinformed on the late-term abortion ban she crusaded against.
1706, respelling of croisade (1570s), from Middle French croisade (16c.), Spanish cruzada, both from Medieval Latin cruciata, past participle of cruciare "to mark with a cross," from Latin crux (genitive crucis) "cross." Other Middle English forms were croiserie, creiserie. Figurative sense of "campaign against a public evil" is from 1786.
1732, from crusade (n.). Related: Crusaded; crusading.