Unusually for me I have this nearly all solved, I have the central unclued answer and the quote, and most of the perimeter. Would appreciate vague hints (!) for:
2d Origin of incredible tall bird soaring. I have ??AR and think there is an E misprint.
4d is making me feel very stupid. Rule by Communist brought about a source of tension ?R?TED. Might have a D misprint.
Ta