Here's the bottom line, airtravel intra-US cannot be subsidized by airtravel outside the country, at best it only subsidizes the intl routes that actually are flown, not help in making money on say a DAL-LAX or ATL-SEA.
The legacies have tried to do this for decades against the LCC's, they've lost more money than all of aviation has made since Wilbur said "clear prop".
Another legacy problem is the work less for more pay attitude instead of work more for more pay, that is a socialistic failure in the making, as evident by every brankruptcy.
The only issue right now is SWA is at the tipping point every legacy was at when they made the decision to step outside CONUS. There will be higher costs, lower returns till they find the sweet spot, and they'll find it with lower cost, lower fares, and higher RASM.