I believe the issue is whether to fund the 2nd Avenue subway and other improvements in the city. No one in the city opposes the LIRR to GCT. People outside the city oppose subway improvments
I won't play the game because your basic premise is flawed. There are most definitely bean counters in the City who watch every cent that goes to the Commuter Roads (including the commuters' own money) and complain. This includes the Straphangers' Campaign. I would like you to cite a single recognizable suburban newspaper or organized group that opposes subway construction (at least on the NY side--I don't see Jersey papers).
And your original question essentially asks the question: Should WE let THEM get something until WE get what WE want. This is the kind of political parochialism that has poisoned planning in the New York region.
Without playing the US vs. THEM game, you could better question how the MTA, its constituent agencies and even its predecessors has spent the money it already had.
Foe example, the frittering away of the $500 million bond (1950) for the original Second Avenue subway (which was to have been from 4 to 6 tracks--nowadays we can't build 2).
Or the 1970's investment in building a series of holes in the ground for the Second Avenue Line (including downtown) when we might have been concentrating on the weakest link in 2nd Ave: 63rd street to a connection with Pelham Bay?
Should the TA have been sinking money into Chrystie Street, and the 6th Ave. express tracks before 2nd Ave.? Or building the 63rd St. tunnel and its super-expensive midtown connections before 2nd Ave.?
For that matter, should the City have lusted after tearing down the 2nd Avenue el while the 2nd Avenue subway was just pie-in-the-sky?
This does not apply only on the subway. Should the MTA/LIRR have spent a fortune rebuilding Harold Jct., which increased reliability but didn't cut running times, before rebuilding the Jamaica station complex, which could have had a significant effect on both reliability and rush hour timings?
But listing the above (a very incomplete list) implies that this is all history. It is not.
By asking the comfy US vs. THEM question, you avoid asking a much more relevant one: would a 2nd Ave. subway be the best investment of major construction funds for the City? I would say not. A permanent replacement and/or supplement for the Manhattan Bridge, consisting at least of a connection between the BMT and the York Street tunnel, and a new tube under the East River is more important.
Second Avenue is a very important project, but it is covered, however poorly, in the short term by the Lex and express buses on 1st and 2nd Avenues. However, southern Brooklyn stands to lose all of its viable rapid transit. It's only a single really bad engineer's report on the Manhattan Bridge away...