I suspect that the future of Avatar isn't actually suppost to be 'our' future but rather some alternative universe.
The clearest example of this would be the Aerospatiale SA-2 Samson, Aérospatiale's helicopter divisons was merged with another company in 1992 to form Eurocopter and the entire company was broken up in 2000. But since the Samson is to us a future aircraft this suggests that Aérospatiale continued to exist into the mid-21th century. This gives a point of divergense of before 1992.
Given that Aérospatiale's breakup was due partly due to the winding down of cold war miltary procurement, this suggests that either the cold war didn't truely end in 1991 or a new threat emerged shortly afterwards. Possibly calls for greater intervention in world poltics, imagine a successful somalia intervention encouraging the US and other countries to go in a sort out any problem they see, leading to the imperialist attitudes suggested in Avatar.
Or possibly Cameron just deciced in the orginal project 880 script the vechile would be from Aérospatiale and just refused/forgot to change it when the company folded. Still it is interesting.
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