When all is said and done CLT will be the largest domestic hub in the system. You need to feed international traffic in the AA system where the demand is. JFK in the north east to Europe, Miami in the Southeast to Latin America, DFW and ORD in both directions including international to Europe and Latin America. CLT was good for USAir before American. I don't know how PHL will end up in the future. PHX was America West HDQ. Long gone now. Too close to DFW. LAX and SFO are perfect gateway cities to the Pacific and beyond. Right now AA has too many hubs serving multiple regions with overlapping destinations. To feed all these hubs you need domestic feeds from smaller aircraft. Early retirements of the MD80's and the 757's plus the recent deferrals of some airbus aircraft does not support all these hubs. One has to realize that CLT, PIT, PHX and PHL worked for USAir, but now we are a different company. JFK, Miami and LAX are prime cities that USAir never had as hubs and finally they are part of the new American. CLT, PHX and PHL will no longer be what they once were because we now have hubs in prime locations. All this is my opinion. What will actually happen in the future? You never know in this crazy world of commercial aviation.