One of the most vexed and vexing questions for a modern economy is that relating to the provision of infrastructure - the range of utilities and services that enable property development to take place to ensure an appropriate quality of life for individuals, neighbourhoods and communities.
For some time, infrastructure provision has attracted intense political debate about who provides it and who pays for it?
Equally important is an appreciation that to be effective, efficient and equitable across different geographies and communities then infrastructure should be strategically thought through and provided to serve specific purposes.
It is nonsensical for infrastructure to simply peter out in the middle of nowhere or not to be connected to appropriate networks. It has to be set in a strategic framework and be integrated with all other facets of the modern world - including the limits set by the environments, including protecting high-grade agricultural land and ecological assets.
The decision to build an off-line restricted access dual-carriageway from Ballygawley to the North West in conjunction with the Irish government was assessed as a good investment when first proposed.
It would have negated the need for Stormont to invest in upgrading the A6 Belfast-Londonderry route as it would have made the M1-A4-A5 corridor the natural route to Derry. However, with significant stretches of the Republic's N2 still single carriageway and passing through settlements, the likelihood of the southern portion between Dunleer and the border being fully upgraded is now much more distant.
The A5 is a reasonable road as is, and would appear to be able to cope with the traffic numbers.
There are obvious areas such as Omagh where a proper bypass is required, and some areas of short dual carriageway would alleviate light traffic's frustration with slower moving loads. Indeed there are much better infrastructure investment opportunities for Stormont.
An immediate concern is for the construction industry in Northern Ireland. To maintain knowledge and experience civil engineering firms need a consistent throughput of work.
The A5 would have been a significant project that would have secured jobs across a range of pay grades. For the North West there is a need for re-assurance that the geographical divide is not also a social and economic one.
In considering infrastructure investment we must consider the longer-term benefits as well as the shorter-term.
Roads are useful when cheaper transport fuels are available, but with the end of low-cost oil we must re-consider how people, goods and materials will be moved. Is it worth investing in the dualling of the A2 if in the short-term it only brings traffic quicker to a longer queue at the Whiteabbey roundabout?
In the long-term will it lie empty when car drivers can no longer fill their petrol tanks?
In the longer-term, unless the electric battery is significantly improved or safer methods for holding hydrogen are identified, the car will inevitably be restricted to short journeys. Transport infrastructure investment must reflect this.
Fuel poverty is a major problem in Northern Ireland and will grow unless infrastructure investment takes place. Stormont has announced the fitting of double-glazing to social housing in its plan for Government. This is to be applauded. However, double-glazing isn't the best payback in terms of reducing heating bills and, if fitted without the adoption of proper ventilation strategies, may cause health issues for occupants. The question does arise as to how well the glazing industry lobbied Stormont compared with the insulation industry?
The School of the Built Environment at the University of Ulster is undertaking research into retrofit of houses so that solutions to creating a zero-carbon built environment can be found. We need solutions to retrofit that involve staged investment in our buildings such as better boilers, insulation and air tightness so that homes can be gradually upgraded to as near as zero carbon as is practicable.
Future heating for hot water and residual heating for homes may come from district heating schemes or electrical, these are infrastructure developments that need research as to how best to deploy and install in such a way that investment has a long life span.
It is ironic that the A5 decision takes place at about the same time as the publication of Plan B - published by Compass, a think tank which comments on economic affairs.
At a time of considerable economic bleakness, with adverse social, community and environmental impacts, and a highly differentiated geography of those effects, this advocacy document suggests an alternative way.
It sets out an investment led economic approach. In other words, it sees an economic recovery through deliberate government investment in infrastructure - and if that can be environmentally sensitive then so much the better.
Together these capture the tensions which lie at the core of current policy making and politics.
The loss of investment raises the spectre of an infrastructure deficit and more worryingly the move away from a strategic approach to economic rebuilding, social well-being and environmental safety.