No offence, but any nation building an unnecessary and expensive improvement to that under-used road would seem misguided, whatever the price of crude oil. The only way it could build the economy rather than depleting it would be if it was going to make a significant difference to the carriage of international traffic. Does any sane individual honestly believe that is going to be the result of this particular road-widening? All the wild speculation about ASEAN helped drive up the price of land and property in Surin beyond all reason. Now look at all the empty business premises, new and old, and the empty homes above so many of them. Consider the over-stretched budgets of those who speculated, those who believed the hype, who opened new businesses including restaurants and bars only to see them fail within a year - and sometimes within a few weeks. Vast amounts are still scheduled to be spent on new government buildings and a railway station. Are there ANY signs that any of them will help bring the false hopes to some fruition? I would suggest that if a fraction of the expenditure on them was directed into REAL education for the next generation, and making efficiencies in the way the country is run, then it would bring far greater and longer-lasting economic benefits to Thai people and those of us who have chosen to live among them. Real white elephants have Royal connotations in Thai culture, but this particular version is neither use nor ornament - to the economy or the ecology of the area - and I would say the same irrespective of the nationality of the people behind it. Read my old posts - I seldom if ever knock the Thai people, and have never thought them dumb, any more than I consider all UK folk to be dumb.
I take your point regarding the current price of oil, but what percentage of the cost of the road works , I wonder, does the likely increase in crude prices represent over the projected lifetime of the surface before it will need to be replaced due to weather conditions?