While Wall Street has been burning, commodity markets have been soaring. Traders increasingly view commodities as a safe haven amid the turmoil in financial markets.

The highest-profile commodities are oil and gold. Recently, the price of oil topped $100 a barrel and kept going, briefly breaching $110 a barrel. It's not surprising, then, that during the recent stock market turmoil, companies such as Range Resources (NYSE: RRC) and Continental Resources (NYSE: CLR) have seen their share prices rise, not fall.

Just a few years ago, gold was all but written off as an investment. Yet it was recently selling for $1,000 an ounce -- a level all but the most loyal gold bulls thought unattainable. The share prices of companies like Kinross Gold (NYSE: KGC) and Barrick Gold (NYSE: ABX) have also risen nicely over the past couple of months (last week's drop aside).

Suddenly, gold is a mainstream investing sport again.

While there is likely an element of speculation in the prices of many commodities, including oil and gold, there are strong underlying fundamentals that suggest the resources boom is here to stay.

The resources boom is alive and kicking
The highly respected daily The Australian Financial Review (AFR) -- the Australian equivalent of The Wall Street Journal -- recently wrote that the "resources boom, the greatest boom in the history of capitalism, is alive and kicking."

I live in Australia. Here, the resources boom has had a hugely beneficial effect on the economy -- we have had 16 years of growth in a row, a housing boom, and a booming stock market (until this year), much of it a result of the resources boom. Our biggest company is mining giant BHP Billiton (NYSE: BHP), capitalized at around $180 billion, making it larger than both IBM (NYSE: IBM) and ConocoPhillips (NYSE: COP).

More than $A550 billion of resources bets
Here the resources boom continues full steam ahead. New mines are being commissioned continually. Old mines and discoveries, uneconomical just a few years ago because of low commodity prices, are being recommissioned.

Data from Access Economics (as reported in the AFR) indicates that exploration expenditure is rampant. There are around $A200 billion of mining projects already committed or under construction, a further $A178 billion of possible projects are pending, and another $A175 billion worth are under consideration.

Boom or bubble?
With commodity prices already at record highs, many people are predicting the resources boom is a bubble ready to burst spectacularly. The commodity sector is notoriously cyclical, and the time to buy is at the bottom of the cycle. We are surely closer to the top of the cycle than the bottom, traditionally seen as the time to sell.

But there are plenty of counterarguments, most of which focus on the insatiable Chinese growth story.

Jim Rogers, investor and outspoken financial commentator, famously predicted the commodities boom years ago. In this 2006 interview, he said "the shortest bull market in commodities I could find lasted 15 years, and the longest lasted 23 years. So, if history is any guide, this bull market will last sometime until 2014 and 2022."

Last year, prominent investor Marc Faber was quoted on Bloomberg: "The up wave of the [current commodities] cycle is likely to last another 15 to 20 years."

So just another 14 or 19 years to go ...

It's China, stupid
Either this is the greatest resources bubble of all time or the insatiable demand from China, the increasing demand from India, plus the usual consumption from huge economies like the U.S., Japan, Germany, and the rest of Europe will continue to fuel this resources boom.

I think it's the latter. The world is experiencing a once-in-a-century boom via China. The country is undergoing unparalleled industrialization, with 17 million people expected to migrate to cities over the next decade. The Chinese economy grew more than 11% in 2007, and China's global economic share, according to investment bank Roth Capital, is now more than 15%.

While there will be some slowing of Chinese exports as the U.S. economy stalls, domestic demand for commodities, driven by new factories, bridges, roads, railways, and buildings, continues unabated. It all adds up to a commodity sector still structured by strong supply versus demand fundamentals.

On top of that, the outlook for the U.S. dollar continues to be bleak. Plummeting U.S. interest rates and the resulting falling U.S. dollar is commonly seen by commodity analysts as very bullish for commodities -- witness the oil and gold prices at recent record highs.

The resources boom is over there
What's most remarkable perhaps is that the resources boom is happening largely outside the United States. There have been no new oil refineries built in the U.S. since 1976, and countries such as Australia, Canada, South Africa, and even China -- homes to the biggest resource assets in the world -- are increasingly shipping raw materials to the developing world.

Our team at the Global Gains newsletter service searches the globe for companies uniquely placed to prosper from the falling U.S. dollar and the ongoing resources boom. One of the very best performers in our portfolio is a 50-year-old South African integrated oil and gas company.

Make no mistake -- Global Gains is not only about resources companies, and it's definitely not about highly speculative golddiggers. But with the U.S. dollar set to continue its fall, the prudent course for U.S. investors is to make companies that generate the bulk of their earnings in currencies other than the dollar a significant part of their portfolios. That's the only way to play both offense and defense.

If you're game for a foreign gain, give Global Gainsa free try for 30 days.

Fool contributor Bruce Jackson wants to know why Americans don't spell famous "famos" and surprised "surprized." He doesn't own any companies mentioned in this article. The Motley Fool has a booming disclosure policy.