Did this "Islamic Golden Age" ever extend much beyond the courts of rulers so wealthy and powerful they did whatever they wanted?Yup; from all I've read about it, such tolerance and open-mindedness seems to have been, not an exception, but the rule.
Was all this supported by police state repression far and wide (including unfriendly clerics)?No, from what I've gathered (in my admittedly scattered and not-very-deep reading), it wasn't.
Why is it so hard for you to believe that they really were pretty good guys, a few centuries back? Has the current wave of general-demonization-of-Islam propaganda already had so much of an effect on you (all), or what?
Islam's response...It isn't that monolithic; that's about as over-simplified as talking about "The Christian attitude to Jews" (or whatever).
...to the citizens of a conquered city who begged that their library be spared: "If what is in these books is not in the Koran, than it is false. If it is in the Koran, then it is redundant".Replace "Koran" with "Bible", and doesn't it look *exactly* like a corresponding mediaeval Christian statement? (And, hey, considering that we're only in the sixteenth century, by *their* reckoning, isn't it *appropriate* for them to be mediaeval right about now...? :-)
On the whole, I think "If what is in these books is not in the Bible, than it is false. If it is in the Bible, then it is redundant" is more typical of Christianity, than "If what is in these books is not in the Koran, than it is false. If it is in the Koran, then it is redundant" is of Islam.