The reason the US doesn't do reciprocity (sp?) deals is it doesn't make any sense for the US airline industry. US airlines are the 800 pound gorilla and so is the US market. It thus makes no economic sense to the airlines to let every Tom, Dick and Mary (or Nigel) fly into US cities when the only thing there is to offer in return is reciprocity in the form of the UK or euro airports and market.
When it finally gets to the point that there
are only 5 airlines and they are all multinational then it won't matter to the airlines but until then there will be no "open skies" because that would not be good for the ATA, and if it isn't good for the ATA it won't happen.