The tram line was paid for locally, through local taxes with a huge payment from the airport. Maybe you should be complaining that your local population aren't calling for you local politicians to fund improvements in the links to the airport, as happened in Manc in 2004.
Remember when I posted a link to local transport priorities in West Yorkshire?
Why would central government fund a scheme that's not even a local priority in West Yorkshire?
The fights are clearly commercial decisions, something you seem to struggle with the concept of.
The reason it won't happen is because their is limited local demand politically and no economic case.
Simple.
Updated: LA you seem very poorly informed...
A new Metrolink line to the Airport is also under construction. It will extend from the South Manchester Line at Chorlton and run on 14.5km (9 miles) of new track via Northern Moor, Baguley, and Wythenshawe to Manchester Airport with 15 stops. The line is planned to open in 2016. The scheme is being financed by local funding as part of the Greater Manchester Transport Fund Programme.
https://www.google.co.uk/url?sa=t&so...Xdc0taImM8BS-A
Seems if you took the time to better understand how the real world operates you'd better understand why it's as it is.
Suppose the question back to you is if you think all areas should be treated equally in terms of infrastructure development, then why should Leeds get centrally funded
https://www.google.co.uk/url?sa=t&so...-Aimprovements when Manc had to fund it locally? Thought you wanted it to be 'fair'?