Looks like Etihad is planning a major expansion to the US...
UAE and US have an open skies agreement. Etihad codeshares wih AA. Why doesn't AA fly to AUH from DFW, ORD, MIA, LAX, JFK or IAD and utilize codeshare/open skies agreement is something to ask Doug Parker...
As an American living in the UAE, I like the idea of preclearance here, though I would have preferred to have seen it in Dubai (Emirates has a greater presence in the US, and UAL and Delta fly here as well).