I don't believe bankruptcy is the only way to sidestep a union contract in the (non-government) arena. A quick search will find "alter-ego" airlines, initially filled with plenty of non-union pilots working under rules that would violate the contracts from their "ego" affiliates.

As to the government union side, check out the $5 million party the FAA managers are having in ATL. That's after 3 years of a unilaterally imposed contract. No strike, no bankruptcy. Without the current government political leadership, it would still be the same.

Those imposed work rules were only one year after (in 2005) sending home the federally employed flight service station folks, some with days to go before retirement, so they could sell the jobs to non-union "alter ego" employees at Lockheed Martin. Those guys may never get their jobs back.

I'm not saying don't fight the good fight. But don't fall prey to union organizer or supporter rhetoric that implies that you're 100% safe in the union. Remember this:

ANYTHING OF VALUE IN YOUR UNION CONTRACT IS SUBJECT TO SOMEBODY WANTING TO TAKE IT, BY WHAT EVER METHOD, LEGAL, QUASI-LEGAL, OR ILLEGAL.