To Americans, of course, it’s the former. But to world oil markets, the latter may be a far more significant indication of where oil prices will be heading this summer.

At today’s pump prices, it’s a safe bet U.S. gasoline consumption during the peak summer driving season will be lower than last year. One of the ironies for U.S. motorists is the relatively low taxation rates on gasoline makes their pump prices more sensitive to rising world oil prices than pump prices in higher taxed jurisdictions such as Western Europe or Canada. That makes U.S. gasoline demand one of the most price-sensitive in the world.

Four dollar per gallon gasoline prices will curb Americans’ appetite for oil, as well as squeeze out a lot of other spending by the U.S consumer. But as the U.S. continues to pare back its oil consumption, other economies will seek a bigger share of the pie from a near static world oil supply. With power shortages spreading in China and Japan, as well as India and Pakistan, demand for diesel fuel is soaring in power-starved Asia.

While few places in North America burn triple digit oil to generate electricity, many places in Asia still do. Even more do when coal-powered grids start to ration power to major industrial users like what is occurring in China right now..

Past power outages have bumped up China’s diesel consumption by as much as another 600,000 barrels/day once power rationing spurs the use of back up diesel generators. And this summer’s power shortages could be bigger than 2004, which temporarily blacked out huge swaths of the Chinese economy.

When you throw in more demand of another 200,000 to 300,000 barrels a day for diesel from Japan to compensate for sidelined nuclear reactors, it is not hard to see nearly a million barrels a day of additional oil demand coming from the power needs of Asia’s two biggest economies. And that doesn’t even begin to include the demand for oil from another 18 million cars on the road in China from new sales this year.

Guess where much of the oil to meet all this new Asian demand is likely to come from?

With little, if any usable excess capacity in OPEC, world crude demand is already on the verge of outpacing world supply. In the resulting zero sum world, conflicting trends in oil consumption between the world’s two largest oil consumers, the U.S. and China, will not be the exception but the norm.

If the Chinese economy is going to continue to increase its oil consumption by 10% a year, another economy will have to cut back its oil consumption by a comparable amount to make room for the increase in Chinese demand.

More and more, that place looks like America.

If the world’s economic outlook is the same as Greece’s, both stock and oil markets have every right to be concerned about valuations. Brutal fiscal austerity and the general strikes and growing social unrest it triggers are not normally the ingredients for a sunny outlook for world oil demand, nor, for that matter, world anything demand. Given where Greece’s economy is likely to be heading, its citizens will consume less oil, not more, in the future.

Of course, it isn’t really Greece that Wall Street cares about. Financial markets are certainly justified in seeing a lot of Greece’s problems in other countries. And they’re not all in Euroland. As I’ve said before in this blog, we’re all PIGS (Portugal, Italy, Greece and Spain) now—at least all the oil-guzzling economies of the old economic order are. Today, the countries whose fiscal futures traders are shorting aren’t developing countries with fragile financial markets but rather developed nations with their supposedly world-leading financial institutions.

For example, the US federal deficit is now a double-digit ratio of the country’s GDP, a statistic that might have an IMF SWAT team arrive if we were talking about the same fiscal situation prevailing in a developing country with a lot of international IOUs outstanding. And the US has a lot more debt out there than all of the PIGS put together. Will American taxpayers soon be asked to make many of the sacrifices Greek taxpayers are being asked to make today? And what will that do for their future fuel consumption? Probably the same thing it will do for the Greeks’.

What markets have yet to recognize is that although the fiscal crises in those economies can only hasten the downward spiral, oil demand had already peaked before they occurred and begun its terminal decline. But in a world where oil supply will no longer be growing (and may even decline, if deep-water fields become off bounds), oil consumption suddenly becomes a zero-sum game. There must be fewer cars on the road in Greece and in the United States if there are to be more cars on the road in China and India.

The fiscal crisis in Europe and the US doesn’t mean the world will want less oil. It just means that global demand will become even more driven by the Chinas and Indias of the world. If you thought global economic growth and commodity demand were skewed to the developing world before all the developed economies ran up massive fiscal deficits, just wait until you see what the gap will look like when those economies have to start paying those deficits down.

Three years ago, it would have told you that global oil markets were at record tightness. Back then, the US president was making a personal pilgrimage to Saudi Arabia to vainly plead for more production. And economists were worrying about the implications for global economic growth.

Today, it seems the goalposts have suddenly moved. After filling up on $4-per-gallon gasoline only two Memorial Day weekends ago, today’s $2.20-per-gallon average gasoline price doesn’t seem so expensive to American motorists anymore.

And suddenly, $80-per-barrel oil is no longer seen by the Saudis as threatening global oil demand, but is instead viewed as a minimum price for their nation to invest in new supply. And as far as my fellow economists are concerned, we’ve heard not even a peep from them about what these types of oil prices may mean for the global economy in the days ahead.

But how much longer can the world pretend that it won’t soon be facing another energy shock, one every bit as challenging as the one it met two years ago? Does anyone still believe the reassuring forecasts from discredited feel-good organizations like the International Energy Agency about new sources of cheap supply, like those that once flowed from places like Prudhoe Bay in Alaska or the North Sea? If so, where is that supply of new affordable oil coming from? Surely not from tar sands or from ultra-deep water fields six miles below the ocean’s floor.

And what will suddenly put the brakes on world demand over the next year that will pull oil prices back from the precipice of triple-digit range? Are car sales about to tank in China and India over the coming months, suddenly halting the otherwise insatiable demand from these countries for more oil? Will OPEC suddenly start charging its drivers and its utilities world oil prices and halt the explosive demand growth in their own economies for the very oil they are supposed to supply to the rest of the world?

Whether we are talking about supply or demand, there is nothing on the horizon to prevent the imminent return of the very same oil prices that put us into the deepest postwar recession yet in the first place.

By the fourth quarter of this year, oil prices will be back in triple-digit range, and by next year oil prices will rise to record highs, taking out the high-water mark of $147 per barrel that was set back before the recession began in 2008.

We’re barely out of the recession, and already we face prices that, just a few years ago, our government, our oil industry and our economists told us we would never see.

Where do you think oil prices will be trading in the future?

Exactly why oil traders and speculators think the data has anything to do with the state of world oil demand is beyond me. I suppose, like Pavlov’s dog, they’re only doing what they’re trained to do. But their training comes from a world that no longer exists.

While the US oil inventories data pertains to the largest oil-consuming nation on the planet, it is no more indicative of world demand than US oil production numbers are indicative of world supply. Both are in terminal and irreversible decline.

It certainly wasn’t US fuel demand that took oil prices over $100 in the first place, and it won’t be US fuel demand that will push them back into that range anytime soon. US oil consumption is almost 3 million barrels per day short of its pre-recession peak.

But the fact of the matter is that US oil consumption will never regain its pre-recession peak, just as US motor vehicle sales will never again see the levels that prevailed before the recession. Ditto for oil consumption in Canada, Western Europe, Japan, or, for that matter, anywhere in the OECD economies.

Back in the 1990s, that kind of demand contraction in the OECD would have foretold a big decline in oil prices, since those countries accounted for almost three quarters of global oil demand. Today, they account for barely half, and tomorrow they will account for even less.

Just as the developing world has long surpassed the developed world in terms of coal consumption, the same is about to happen with respect to oil. Between explosive growth in oil-thirsty economies like China and India, and OPEC’s voracious appetite for its own fuel, OECD fuel markets are becoming increasingly marginal. That’s why Saudi Aramco is far more interested in securing long-term supply contracts with rapidly expanding domestic oil markets in countries such as China and India than in supplying shrinking oil markets like those in the US.

In a world where affordable oil supply will soon peak, if it hasn’t already done so, global oil consumption quickly becomes a zero-sum game. As China moves from consuming 8 million barrels a day to 10 million barrels, and OPEC ramps up its own daily consumption from 10.5 million to 12 million barrels, somehow, somewhere else in the world, there must be a corresponding decline in oil consumption. That somewhere else just happens to be the US market and the oil markets of the other OECD economies.

So instead of thinking that a decline in US oil consumption means a build-up in global oil inventories, just think of it as freeing up another barrel to be guzzled in China or the Middle East.

Photo ops for local schmoes trying to make it big on a world stage don’t abate a single ton of carbon going out into the atmosphere, and neither does anything else coming out of that environmental summit. Nor could it, really, when over half the participants, including the most egregious carbon emitter of them all—China—didn’t even want to be there. With energy consumption per capita at a tenth of ours, the only thing that interests countries like China is emitting a whole lot more. That country may lead the world in clean wind power, but it also has more coal plants spewing emissions than the US, UK and Japan combined.

So it’s only natural that people in this part of the world would be skeptical, if not downright cynical, about trying to go down the multilateral path ever again.

But just because North Americans have lost faith in international environmental summits doesn’t mean that environmental—and, in particular, carbon—concerns don’t factor more and more into our economies and our everyday lives.

Try setting up a brand-spanking-new coal-fired power plant, like the 800 China and India will have on the go, and see how far you get in the approval process. With the exception of major coal-producing areas like Wyoming, West Virginia and Alberta, you can’t get new coal-fired facilities licensed anymore, not even in places like Texas, which still get nearly half their power from coal, let alone in holier-than-thou states like California.

Unlike the plethora of platitudes and pontifications that came out of Copenhagen, North American power users put their money where their mouths are. It costs a lot more to generate a kilowatt of electricity from natural gas, or, even more, from running a nuclear power plant, than from burning still-abundant but carbon-dirty coal.

You can stand wherever you want on the global climate change debate. (I’m no climatologist, but it seems to me the recent images of open water in the once-frozen Arctic Ocean are pretty compelling evidence, even if it’ll take another 300 years to melt the Himalayan snow cap.) But whether or not you believe in anthropogenic global warming isn’t really the point.

The point is that we all live in one world, and what’s valid at one end of the world should be valid at the other end. There can’t be ever-more-expensive carbon abatement restrictions on the side of the planet that thinks its emissions are responsible for adverse climate change, while on the other side there’s a doubling in global coal consumption over the next two decades.

If we think global warming is for real, we need to put a price on our own carbon emissions, and slap a carbon tariff on everyone else’s.

Otherwise, why can’t we build coal plants, too?