Whatever happens to demand, the oil market is more vulnerable to shifts on the supply side from both the diverse private sector liquids producers and from OPEC’s cartel power. Fears over weak economic growth leading to slower oil demand expansion has led to concern that oil prices are too high and overstate the market balance. But global oil demand growth is still moving forward, old fields are still declining and a surge of unconventional oil such as American shale oil and steadily growing biofuel and tar sand production is not enough to deliver a soft market.  On the other hand, industry perceptions of the future value of oil and probably for natural gas too is likely to encourage sufficient liquids capacity investment (whether it be deep water, shale oil or other resources) to allow capacity growth to at least match the net decline rate in producing fields. How soon, how much, where and from whom the spending will come is hard to plot, but it is probable that OPEC will not be ready to invest in new and unused spare capacity simply  to ease pressure on oil prices for importers.