Yes, Khitan were fallen state at that point.
Propping up Khitans against Jurchens, in exchange for those mountain passes would've been good idea. Regrettably, Songs would be unable to pull it off, even less than partitioning Khitan with Jurchens. Well, maybe if Yelu Dashi was fighting Jurchen rather than waste his time holding off Song.
Things weren't black or white, but Song were such a big dicks, in their external and internal policies, for me to not feel terribly sorry their empire fallen.
Good and evil are relative, but being dick is not allowed.
I don't feel sorry for them either.The blunders conducted by the Song elite was so stupid that it was actually quite hilarious.For the most part,it was run by a group of cowardly,self-interested morons.
I have to retract my earlier statement that they weren't ambitious.There were actually two groups of people in the Song Dynasty--unambitious defeatists and those who were ridiculously ambitious and tried to achieve results without investing too much in it.They've always wanted the Sixteen Prefectures,problem was that a lot of the ruling elite were just way too cowardly and self-interested to pull their shits together and get it back.The fact that they didn't have the will to revitalize their army and tried to get the Sixteen prefectures back through cheap tricks like sucker punching the Khitans definitely shows this.If the Song Dynasty aided the Khitans,perhaps the Khitans won't be screwed.Though will the Khitans be willing to accept this?The Sixteen Prefectures as mentioned was the wealthiest region in the Khitan Empire.Their past enmity with the Song Dynasty definitely did not help relations.
The ruling elite of the Song Dynasty was always too afraid and jealous of military officials who were successful,and way too afraid of foreign enemies who were strong--thus they were often maintained complete pushovers when it came to war.Yet,they get ridiculously ambitious whenever their enemies seem to be down--often trying to bite off far more than they can chew.
Didn't Zhezong reinstitute New Policies? Those look suspiciously like Great Leap Forward...
It was,though at the very least Zhezong was well intentioned and for the most part a capable ruler.Compared to Huizong,the man's a saint.Huizong was a great artist,but a horrible ruler.Even without the Jingkang Crisis,he would still be a pretty horrible ruler.