ExxonMobil has a loaded gun pointed at the U.S. natural-gas market -- and it isn't the only one.

The ammunition is liquefied natural gas. Exxon is scheduled to start up another three LNG projects in Qatar this year. They will produce more than three billion cubic feet a day of natural gas and freeze it for transportation. Europe and Asia are potential markets. But the U.S. could be a magnet for LNG cargoes, despite not really needing it, a paradox that spells low prices.

LNG is joining up the world's hitherto largely regional natural-gas markets just as demand is faltering. Declining natural-gas production in countries such as the U.S. and U.K., and rising energy prices, prompted LNG production and receiving terminals to sprout on coastlines around the world. Some 28% of internationally traded natural gas was in the form of LNG in 2008, according to data from BP PLC.

Two things have turned this scenario on its head. One is recession. The other is the development of unconventional natural-gas resources in the U.S., leaving it oversupplied for now. Several Wall Street analysts expect inventories to reach the maximum capacity of about 3.9 trillion cubic feet later this year.

So why would anyone ship LNG to the U.S.? In part, it's simple economics. Many projects were sanctioned and financed when lower natural-gas prices prevailed.

In Exxon's case, valuable liquids also produced in its Qatari projects take the market break-even price of the natural gas itself "towards zero," says Deutsche Bank analyst Paul Sankey. Factoring in processing and shipping costs, that gas can be landed in the U.S. for less than $2 per million British thermal units, reckons Noel Tomnay, head of global gas at Wood Mackenzie. The current Nymex price is about $4. Futures prices for this winter are closer to $6 per million BTUs.

Competing markets also look oversupplied. Wood Mackenzie estimates annual demand in Asia east of India will rise by 1.3 trillion cubic feet by 2015. New projects targeting the region and close to final investment decisions amount to more than two trillion cubic feet of capacity.

In Europe, the prevalence of long-term pipeline contracts limits the size of the market up for grabs. Wood Mackenzie estimates about 4.9 trillion cubic feet of discretionary piped and liquefied natural gas a year will compete for a market half that size over the next three years.

The U.S., with its large, liquid natural-gas market will be a natural destination for this surplus LNG. As a cap on prices, this effect of globalization in the natural-gas market is great news for customers.

In a buyer's market, though, higher-cost sellers suffer. A big increase in low-cost LNG supply would displace some U.S. natural-gas production. The average U.S. field requires a Nymex natural-gas price of $7.79 per million BTUs to earn a 10% return on capital, according to Jonathan Wolff at Credit Suisse.

Yet, as Mr. Wolff points out, natural-gas drillers' capital expenditures are still outpacing cash flow, as they have since 2006. The number of operating natural-gas rigs actually rose last week after many months of declining.

Increasing globalization means a bigger range of factors affect U.S. natural gas and the fortunes of its producers. An extended spat between Russia and Ukraine this past winter, for example, would help draw more LNG cargoes toward Europe.

Barring this, prices and drillers will likely remain under pressure. A question haunting the sector is why majors like Exxon haven't rushed in to scoop up distressed companies sitting on large U.S. natural-gas reserves. The answer may be that, with more LNG pointed at already weak markets, they can afford to take time, and take aim.