Good points Trapper, You are correct that practitioners have made a real and positive difference in some cases. Just in case you think I'm some kind of mindless bigot, I don't believe that Faith is a bad thing. I have it myself.
I will not refute that thanks to the christian church/islam/etal being around for 2000 years or so and having a respect for scholorship, where it did not disagree with the leaderships view of the world (see Gallileo and others), that they have been solely responsible for the preservation and continuance of learning in humanities darkest days.
However, where an organised religion has had political power, the results have been, shall we say, messy. What do you think paid for all those nice churches, mosques, temples, paintings etc?
In the round, over the last couple of millenia, organised religion has been used by powerful people as a tool of oppression and a neat excuse to rape and pillage. With respect, athiestic systems such as china and russia bear striking resemblances to other societies in history that have revolved around a single, rigidly enforced, philosophy/dogma. They also both have reverence for the annointed prophet, Lenin, uncle Joe, Moa etc. Both sides of the same coin you might say. I am making the point that humans aren't nice to each other and some, given the opportunity, make very effective use of organised religion or dogma as a tool to further their own interests.
Go to a library with a history section of reasonable quality armed with the questions below.
1. Has organised religion co-ordinated, condoned, profited from or encouraged the masses to support wars of acquisition?
2. Has organised religion been used as an excuse to oppress people in manners that directly contradict the teachings of that religion?
3. Did organised religion profit hugely from this?
4. Has organised religion used an ethnic group as a scapegoat when a their all powerful godhead has visited a natural disaster upon the populace?
5. What has been the reaction of the leaders of organised religion/the Party, whatever, when their philosophy/dogma is challenged? Hint: Spanish inquisition, witch burnings, the Gulag etc, etc.
6. Has it been the case that, if enough money was passed over, one could have ones misdeeds forgiven or that, inversly, if one failed to make ones proper contribution then one could well be consigned to eternal damnation?
I'm a man of faith but the god I believe in isn't short of a buck or two and doesn't need acts of street robbery writ large to help us worship.