At the time of reading this post of when I clicked the thread, your post time is 13:01 and my computer clock says 13:00. Yer a wizard.
Anyway, yeah it's quite possible they treat Americans differently. Stockholm Syndrome is more than just befriending them though, infact it might even have nothing to do with being friends. It's more the whole your mind being fucked and then mistaking "not being beaten" for "them being kind to me" and from there, sympathizing and maybe even defending the actions and mindset of your captors.
I had the privilege when I was at school of them having a society set up where famous people would come in and talk. And I mean worldwide people not make shift celebrities, intellectuals rather than plastic people. An example was Sir Nick Scheele as he went to my school (he died in July, involved in British auto manufacturing). Anyway one of the guys who came in and did a talk for an hour was a guy called Terry Waite who was a British hostage negotiator in Lebanon, before he got held as a hostage himself.
http://en.wikipedia.org/wiki/Terry_Waite
He was held hostage for over 1700 days. He spoke about his time in captivity and battling Stockholm syndrome and the treatment that his captors gave him. I wish for the life of me I could remember more words that he said and phrases used to describe (this was like 3-4 years ago now) but my impressions and thoughts over such an issue are quite sculpted, I'd read about it before but hearing someone talk about it who experienced it was quite eye opening. Was far and away one of the most interesting talks we had.