Prices have risen 50 percent this year, spurred by strong demand, tight production and geopolitical uncertainty in many oil-producing regions.

Mr. Shackelford said the economy was being held back by geopolitical uncertainties, including the threat of a war with Iraq.

Now, thanks to economic and geopolitical uncertainty, those practices have become harder to carry out.

"Greenspan's made it pretty clear that he thinks the main problem is geopolitical uncertainty from which we'll recover."

Lately, the threat of war with Iraq, rising oil prices and other geopolitical uncertainties have been dragging it lower.

But because the current bull market hasn't faced such a correction - despite geopolitical uncertainties, natural disasters and record energy prices - big risks remain.

Still, despite the market's recent rise, many deal makers said companies were likely to stay on the sidelines simply because of the geopolitical uncertainty.

"On top of that is the geopolitical uncertainty," he said.

There is broad agreement, however, that heightened geopolitical uncertainty will make it difficult for the market to sustain a broad upward move for long.

And we haven't even talked about the geopolitical uncertainties.