The unions would rather see this company fail than give up one benefit or goodie. Then, when the whole thing comes crashing down, the unions will run to the government to make good...
The company has already failed. Allowing it to come out of Bankruptcy will propagate its disease through the rest of the industry. The company should be liquidated completely so there 's less competition for the other carriers that have survived so far.
There is a role for the feds here. If they stepped in and forced the liquidation of United and had the other airlines assume the pension debt (with a little help from the feds) you could save the pensions for those close to retirement. You would also help the health of the other airlines.
This would be similar to what Greenspan brokered in the Financial world when that hedge fund (the name slips my mind) went belly up on a trillion dollars worth of positions.