If crude-oil production has peaked or is approaching a peak — an idea that has risen to the status of religious faith at Gristmill and other greenie blogs — one would expect the “smart money” (i.e., the speculator class) to snap up oil futures.

And that is precisely what’s happening, according to today’s Wall Street Journal.

The paper reports today that crude-oil futures leapt $1.35 a barrel yesterday, settling at $68.74, or just a bit more than a buck away from the post-Katrina high.

The rally is partly rooted in brute geopolitics: talk of a U.S. attack on Iran and ongoing strife in Nigeria. But the larger picture may be structural, the Journal reports:

In a phenomenon that could still intensify, big institutions and everyday investors around the globe are adding commodities to their portfolios, hoping the bull market in natural resources will continue. Many of the newcomers are investors who use index-based strategies to, in effect, buy and hold in a field they previously found too complex and risky. [Emphasis added.]

Hoping the bull market in natural resources will continue. Wall Street is signaling it thinks the “bull market” in crude is (in Street argot) “secular,” not “cyclical.” That is, that the price of oil is rising because of structural changes in supply and demand, not short-term oil-company or OPEC manipulation. Investors are snapping up oil-futures contracts because they believe oil is cheaper now than it will be in the near or mid-term future.

Now, Wall Street is fully capable of sending out false signals. A lot of media attention during the late 1990s tech bubble focused on the irrational exuberance of day-trading teens and grannies. But many big-time institutional investors (the sort who run giant mutual funds, retirement funds, etc.) bought the idea that advances in communications technology had created a “New Economy” that overturned the old lessons of boom and bust. (Indeed, Alan Greenspan himself, who for reasons I can’t fathom became a sort of hero to liberals in the 1990s, came close to endorsing this view more than once.)

In 1999, the “smart money” piled into ultra-pricey telecom, networking, and “new media” shares. Anyone who followed behind came to regret it bitterly in 2000.

So what to make of the signal on oil?

First, peak-oil adherents must remember they’re not seers. You have no real idea what the future holds. It’s undeniable that with crude near $70, U.S. conservation efforts a joke, and big-oil profits swelling, new discoveries could be made that ease supply concerns and delay a peak for a while. That could drive prices down, and make fools not only of oil-market speculators but peak-oil types as well.

That said, it’s notable that big money is piling into oil speculation. That means peak oil’s reputation as a fringe theory is looking more and more frayed. The denizens of Oil Drum, et al, officially have company on the corner of Broad and Wall in lower Manhattan, as well as in its midtown skyscrapers.

Meanwhile, the WSJ article also discusses the bull market in gold — which typically rises as a hedge against inflation but is now surging despite a sustained period of low inflation. The Journal refers to “some investors in Asia, the Middle East and elsewhere … hoarding gold.” If investors in Asia and the Middle East are dumping the dollar — which gushes into their economy as payment for consumer goods and crude — in favor of gold, that could spell real trouble for the U.S. economy.

Right now, the U.S. economy hinges on dollars from the Mideast and Asia being recycled into stuff like U.S. Treasury bonds, stocks, and, well, port-patrol companies. (Remember, since the embargo of the early 70s ended, OPEC has only accepted dollars as payment, and dutifully recycled those greenbacks in U.S. assets.)

If those investors are getting nervous about the dollar and plowing significant cash into gold, the U.S. Fed will be forced to raise interest rates — and that could send the shaky housing market over a cliff.