There are unassailable grounds for very-long-term optimism, for the Spirit will not in the end be mocked by the powers of hell. (Thus women's ordination is absolutely guaranteed, ultimately!) The problem is, we have the Slavery of Israel in Egypt and the Exile of Israel in Babylon as our primary scriptural models for the Good eventually winning over evil, that those are hellishly long cycles. Ergo, you short term pessimism has an equally solid scriptural foundation, it would seem. ;-}