Politicians have a key role of in pushing forward the rail possibilities of urban regeneration. The best can be the intelligent client, the leader in more than title, whereas too many will only have a short term view.
In the public perception of city governance the two issues of transport and crime are probably the key defining characteristics of a city and therefore also of its mayor or leader.
In terms of taking a long term view, transport infrastructure can shape a city for centuries to come. Consider the city and its river or port: trade relied on boats for many centuries before roads and wheeled transport. The city often started where the river was just narrow enough to cross and just wide enough to sail away. Roads, canals, railways and airports have all since both shaped and grown cities.
At the UK level for rail, the politician many would regard as the intelligent client of recent years would be Lord Andrew Adonis. He constructed a cross-party consensus for rail investment, and not just for high profile projects such as HS2 but also the mundane but essential task of rail electrification. Unlike some of other ministers he started with a vision rather than a spreadsheet. Putting electric wires above the track makes sense for so many reasons (pollution, climate change, faster journeys, further destinations, reliability, cost). But some previous transport ministers even felt proud in justifying their department having no investment plans for further electrification.
And having a capable transport minister at the national level helps politicians at the city level, especially cities outside London, to take their city vision forward.
London has its own legal powers to organise transport that are denied to other UK cities, and historically has had a first call on national rail funds for grand projets such as ThamesLink (north-south), CrossRail (east-west) and HS1 (international).
City-regions such as Greater Manchester have led the way in “pushing the envelope” of rail development and urban renewal, with both tram and train, by using political soft power to make up for hard legal powers.
Somewhere there is a political book to be written on, the Association of Greater Manchester Authorities (AGMA), public (mass transit) transport and urban regeneration and renewal from bus deregulation in 1980s to Metrolink and HS2 in 21st century. The lessons would be enormous, in my view.