There is a big difference between doing politics and second guessing alternative courses of history. Politics, in my book, involves debates about possible courses of action (e.g. are we going to have public health care or private health business) and claims justifying those courses of action (e.g. social justice vs. profits before people). All such possibilities share same ontological status, even though their probabilities of implementation may differ markedly.
Second guessing alternative courses of history, otoh, involves pitting conjectures against empirical facts. It reminds me of a certain Scottsman who, upon hearing from his son that he run behind a bus to save 5p on the fare, replied "You moron, you should have run behind a taxi and save 5 pounds."
wojtek