This is another of those well intentioned, but historically obtuse and completely unnecessary things people sometimes do. Really, why does the city of Jerusalem have to help people celebrate Christmas? Leaving aside the whole Jewish state thing, what civic purpose does it serve for a municipality to hand out trees? And going back to the whole Jewish state thing... are these people nuts?
I hope this is a hoax. Maybe I'm being pranked - or better yet, maybe when the Christians showed up at the Jaffa gate there was nothing there.
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