In Chicago, gas prices have now topped $4 a gallon. Americans all across the country are struggling to fill up the tank. Companies are even pitching in gas money to help their employees out.

The high and rising price of oil is causing real pain in the heartland. . . and yet the view looks quite different from the Middle East. Chakib Khelil, the Algerian oil minister and president of OPEC, has flatly stated that "there is no shortage."

The oil minister of Qatar is even more blunt. "The market doesn't need more oil," he says. Hussain al-Sharistani, the oil minister of Iraq, takes the strangeness even step further. "There is more oil in the market than consumers want," he argues. (Which begs the question: Which consumers exactly?)

There is obviously plenty of bad news in crude oil's meteoric rise. But the bright side is, real pain means the U.S.A. -- and much of the world -- is finally on the cusp of real change. That means profit opportunity on a major scale.

A few weeks ago, OPEC members seemed to shrug their collective shoulders at the thought of $200 a barrel oil. President Khelil points out that much of the price rise is due to a weak dollar. (Every one percent decline in the dollar's value, OPEC estimates, increases the price of crude by $4 a barrel.)

So the dollar is one major culprit. But there are many other small factors that add up.

For example, China, after suffering through its worst earthquake in decades, has had to shut down mines and wells for safety reasons. Apart from the terrible human tragedy of more than 34,000 lives lost, this can only add upward pressure to oil prices.

In South America, Venezuelan oil exports recently dropped to a five-year low, and evidence is mounting that the country has become a state sponsor of terrorism under Hugo Chavez.

In Nigeria, rebels continue to keep oil and gas production on a knife edge. In places like Russia and Mexico, oil and gas output is declining at an eye-opening rate.

The little things pile up; if it's not one thing, it's another. This is generally the case when supply and demand are so tightly matched there is almost no margin for error. That's where we stand now in terms of global oil demand vs. available daily supply.

It's not rocket science to see how all these factors add up to $127 a barrel oil. For years, naysayers have been telling us that the price of oil was about to collapse and head back to 'cheap' any day now.

Of course, what was cheap just kept edging higher and higher. First it was $25 a barrel. Then it was $35. Then $45, $55, $65 . . . And now we're at the point where $85 or $90 a barrel oil would probably seem 'cheap' relative to today.

The supply side of the equation is tough and getting tougher. And when we look to emerging markets, it becomes clear that the demand train isn't slowing down.

The US consumer might be spent, but consumers in other countries are just rolling up their sleeves.

For example, Bloomberg reported last week, "China's retail sales climbed at the fastest pace since at least 1999, signaling that domestic consumption may help to buffer the world's fourth-biggest economy against an export slowdown."

At the same time, Thailand reportedly booked its fastest growth in two years in the first quarter of 2008.

A key debate these past few years has been whether or not domestic demand growth would kick in strong enough, allowing export-heavy regions of the world like Asia to become captains of their own economic fate. The evidence suggests this is happening.

Then add to that mix the fact that shopping malls are spreading like wildfire in Russia, cheap cars are conquering India, Southeast Asians are doubling and tripling the amount of meat in their diets, and so on.

For much of the 20th century, the Western world threw a party that the rest of the world missed out on. Now that the West is miring itself in economic slowdown, ROW (a common Wall Street acronym for "rest of the world") seems to be saying, "No thanks. We're not much interested in your pity party, either� but we do intend to get our fair share of those resources you've been hogging."

Again, there is plenty of good news, too.

High oil prices may be here to stay, but the reasoning behind this phenomenon is not all bad. It's a good thing for ROW to be coming on line� to see new wealth being created, new economic breakthroughs, new dreams of escaping poverty and hardship on a grand scale.

And here in the land of plenty (the United States), it's good to see habits truly changing for the first time. It was a phenomenon itself these past few years how stubborn the American consumer seemed to be in the face of rising gas prices.

No matter how much pain was felt at the pump, we just kept driving. The gas-guzzler culture seemed to be bulletproof. Ford Excursions and Chevy Suburbans just kept rolling off the lots.

But that isn't the case anymore. Americans are finally starting to ditch their SUVs and -- miracle of miracles -- even pay more attention to things like cheaper transportation and mass transit. Those who decided to live 50 miles from work to save $30K on the mortgage payment are rethinking their options.

Political will is building to do something about the intense pain of high oil prices -- and not just band-aid solutions, either. The naysayers and the Pollyannas have finally been forced to wake up and smell the petrol.

This is all good stuff� and it all represents how change is supposed to happen in a free market system. The unofficial motto of capitalism -- and mother nature, too, for that matter -- could be "If it ain't broke, don't fix it."

For the longest time, America felt rising energy costs were a pain in the butt, perhaps, but really no big deal at the end of the day� and so not much changed. This was only rational, because changes on a huge scale, changes involving a nation's way of life, are never easy to bring about. It often takes a frying pan to the face to bring about that kind of change.

For investors, the really good news about $127 oil is the massive wave of investment opportunity that is about to be unleashed.

Wall Street, as you hopefully know by now, is a deeply psychological beast. The markets are ruled by fear and greed, and thus so is capital flow. Money is supposed to rationally flow to where it can earn the highest return, but sentiment and emotion play a big role, too.

For the past few years, there has been an undercurrent of complacency� a sense that, yeah, oil prices may be high now, but they'll fall back again. Things will be the same� maybe a few things will be different, but nothing will really change.

That complacency is falling away now. Every morning that oil continues to trade at $100 a barrel, it gives Wall Street another chance to sit up, rub its eyes, and collectively say, "Holy @#$#@! Oil is above $100 a barrel! And that probably isn't going to change!"

This means very big things for alternative energy technologies -- not the crackpot ones, but the ones that are already viable (and in some cases already profitable). We're seeing clear example of this as Silicon Valley venture capitalists pour hundreds of billions of dollars into 'cleantech,' and as serious -- and seriously wealthy -- entrepreneurs fund more and more ambitious projects.

We're seeing major investment opportunities pop up all up and down the scale -- from companies with radical new solutions, to companies with old as the hill solutions that just make a heck of a lot of sense, to companies that will profit from this sea change in ways most people never even thought of.

So don't fret too much when President Bush comes on TV and makes apologies for the Saudis, or when crude laughs in the face of band-aid production commitments like an extra 300K barrels a day.

The pain of high-priced oil is here, no doubt, and that pain is real, and is only likely to get worse. But that's how massive scale change is created, and that's how massive investment opportunity is created, too.