Rationality (n.) is abandoned the moment you set up an -ism around a thinker; the rational question is what in his work to keep, fix, or drop.
Rationality (n.) in state planning assumes that human survival counts for little beside short-term power and wealth.
Rationality (n.) belongs to the cool observers, said Niebuhr; the common man follows faith and must be steered with necessary illusions and emotionally potent oversimplifications.
Rationality (n.) within a lunatic framework is still a prescription for disaster: each step makes sense, and the destination is ruin.
Rationality (n.) would expect the richest, best-placed societies to lead the rescue of the planet; capitalist democracy's lunatic version has them leading the plunge.