OK, we don't seem to be able to halt the slide in T&Cs due to the combination of UK/EU industrial law and the willingness of too many people to believe the spin the FTOs put out...
So back to the OP's question...
I have come from/still work in an industry which has a very strong union basis and has the workforce interests still at heart for the majority of the time.
This does not seem apparent in the aviation industry... Can anybody shed some light on this?
Personally I've found my union very good at dealing any individual issues I've had, and generally OK at a company level (though many disagree). Where I do feel they really do fall down is at a strategic, national level where they don't appear to have any clout. One example being the way aircrew are still handled when going through security ex the UK, compared with the treatment in the likes of the States.
If I recall things correctly following one of the security scares a while back the UK Musician's Union got a sweetheart deal for it's members on hand baggage ( extra allowance, "tools of the trade") whereas everybody else, including crew was being messed around left right and centre TFN and beyond.....and it's still liquids, gels, iPads, and laptops out........