Certainly the hemming and hawing with the Bush administration and its European allies over uranium enrichment carries the prospect of a future payday. This week the United States and its European partners came up with their most generous offer yet: Light water nuclear reactors, access to U.S. and European aircraft parts and U.S. agricultural technology.

But the months and months of bluster and bravado between Tehran and Washington maintain a good deal for President Mahmoud Ahmadinejad -- a deal that he must not be particularly eager to part with.

That good deal comes into focus by looking at Iran's oil production and the skittishness of global commodities markets. The Organization of Petroleum Exporting Countries says that in April Iran produced 3.88 million barrels of crude. That's a daily average output of some 128,000 barrels. Now factor in the notoriously jumpy world energy futures exchanges. Virtually every time Condoleezza Rice or her opposite number in Tehran talk tough at each other - in front of television cameras - the price of crude oil ticks up, sometimes by several dollars.

If, for the sake of discussion, one assumes that high-quality crude oil is worth $70 per barrel, one need only estimate how much of that amount reflects fears of future supply disruptions to see how such fears are already a good for Iran. Suppose that of the current price of crude oil, $5 is attributable to traders' and refiners' fears that Persian Gulf supplies could be jeopardized if the United States and Iran went to war. In other words, prospects of a supply disruption, if current negotiations fail, warrant a premium of $5 on each barrel of crude that has to be shipped by tanker out of the Persian Gulf.

On a monthly basis, that $5 premium in the price of each barrel of crude oil translates into about $19 million per month for Iran in extra revenue.

Of course, $5 may be too much to lay at the feet of this particular diplomatic standoff. Or it may be too little. One way to "guesstimate" what the premium is actually worth on the New York Mercantile Exchange or London's International Petroleum Exchange is to estimate how much the price of crude would fall if there were a formal agreement between Tehran and Western nations on Iran's nuclear program. The price would doubtless fall more than the $1 it declined when Abu Musab Zarqawi was killed this week.

The key point is, seemingly endless diplomatic dithering with the West maintains enough uncertainty in New York, Tokyo and London, among other cities, where futures traders buy and sell crude, to create a premium for Iran.

And frankly, Iran could use the money. Its production is sliding, with the decline from March to April exceeding 41,000 barrels. Sales, too, of their predominantly heavy crude are lagging. In fact, last week the National Iranian Tanker Co. chartered two more very large crude carriers to store more unsold crude. That lifted the company's total floating storage capacity to 18.4 million barrels, almost five months of production.

Still, there may be a point of diminishing returns for Ahmadinejad's calculated ambiguity on nuclear energy.

"High oil prices over last few years have given Iran and other countries a sense of empowerment," says Antoine Halff, vice president of energy research in New York for Fimat USA. "There's a certain degree of 'petro-arrogance' in Iran and in other countries.

"Ultimately, though, political instability is not something investors like very much, so in the longer run tough talk by Iran undermines its chances of attracting needed investment to develop its resources."

In the meantime, Halff said he expects more of the same from Iran.

"Iran has been carefully balancing threatening statements and reassuring statements, and deliberately so, to keep the market on its toes. We'll see a lot of this in the next few months.

"In order for the oil weapon to be effective, Iran's position has to remain opaque and any statement that would be too clear would undermine Iran's bargaining power. It would deprive Iran from being a player (so) I think we're going to see some contradictory statements going forward."