Putting public money into the bus is one of the biggest bargains in transport policy, yet it has been one of the biggest losers from recent trends in transport spending. This makes little sense given the Urban Transport Group’s latest analysis, which shows that supporting bus services aligns with the policy goals of 12 of the 25 different departments in Whitehall.

And it’s not just the departments you might expect. Buses tick the boxes for the Department of International Trade because the British bus manufacturing industry has an impressive export track record. The bus meets the goals of the Department of Work & Pensions, such as providing access to opportunity. It helps out DEFRA because buses support rural economies.

And the bus supports the aims of the Department of Health and Social Care as buses promote physical activity, give older and disabled people independence and because they could play a greater role in a more efficient approach to non-emergency patient transport. In short, every single pound that supports bus services cuts congestion, while contributing to numerous wider social, economic and environment goals. Not many other modes of transport could tot up all these benefits.

But without public support for bus services, labour markets will shrink and more people will be unable to participate in the economy; skills and apprenticeships will be hit because of reduced access to further education. High street regeneration will be damaged through reduced access to town centres, and there will be increased pressure on congested road networks as bus users migrate to the car. And there’ll be public health impacts from more isolation and loneliness, and less physical activity. The young will be hit hardest. A divided society will become more divided.

Despite these risks, that hasn’t stopped all six sources of bus funding being cut back in recent years. This in turn, has given an unhelpful shove in the back to a mode which was already tumbling down the slope, plummeting towards the cliff edge in too many parts of the country.

Meanwhile, Highways England has more money that it can spend to expand inter-urban road capacity which will continue to pump more traffic into cities that don’t want it, generate more car-dependent sprawl, worsen air quality, increase carbon emissions and replace big traffic jams with even bigger traffic jams. An extra £500m a year for buses, for example, would be less than 2 per cent of the annual revenue to Treasury from fuel duty.

It’s not just the total amount of bus funding that is the problem however. Making things worse is the convoluted and uncoordinated way in which buses are funded by different Departments, with no sense across government of the cumulative impact of their different decisions.

So, arguably as important for bus funding as the Department for Transport, is the Department of Housing, Communities and Local Government (which indirectly funds concessionary travel, as well as those services which operators won’t provide commercially). And then, in a separate box altogether, is over £1bn of Department for Education funding for schools transport.

All of which makes bus funding the transport equivalent of the Schleswig Holstein question – about which Palmerston said only three people understand it, one of whom was dead, the other mad and the other had forgotten all about it. Put bluntly, it’s a bad way to fund what is a very good thing.

The Treasury’s Spending Review is expected to run the rule over the Department for Transport’s main source of bus funding, the Bus Service Operators Grant, which provides a rebate on fuel duty. The mood music in Whitehall about protecting bus funding is far better than it was last time it was scrutinised in a Spending Review. But with the bus in sharp decline and punch drunk from previous funding cuts, now is the time for something more ambitious than tinkering and holding the line.

Jonathan Bray is Director at the Urban Transport Group.