DAL4EVER has a good point but I doubt it will be the European carriers s/he mentioned. AF has lost a lot of money on this year's 1st quarter cting high fuel price as the chief reason. LH and BA are still profitable but won't be at 150$/bbl.
Sadly the Middle Eaestern carriers don't have to worry about the price of fuel. Some Asian ones have so much cash on hand that they will be well positioned to buy a failing US major or take over its route system or part of it.
Unless things change, within the next 2 years I can see Singapore Airlines with a major hub in IAD and Emirates or Etihad with one in MSP.
Just my 2 cents.