Some say it is the new Meryl Streep movie about Margaret Thatcher coming out in time for the 30th anniversary of her splendid little war.

Others claim it is the posting of the heir to the British throne and his air force helicopter and the deployment of the world's most advanced new warship and nuclear missile submarine to those cold South Atlantic waters.

Observers of Argentine politics say it is all to do with the pre-election opinion poll numbers of President Cristina Fernandez de Kirchner. And the local media regularly assert that the Obama administration wouldn't support their traditional British ally as President Ronald Reagan did during the Falklands war of 1982 when Thatcher sent a battle fleet to retake the islands from the Argentine invaders.

The real reason for the recent saber rattling in the South Atlantic is likely to be revealed this week when Edison Investment Research delivers a newly leaked study suggesting that Britain stands to receive a tax windfall of $180 billion from renewed prospects of more than 4 billion barrels of oil to be recovered around the British-owned islands.

Forecasts of the Falklands oil wealth come and go. Only last month, British Energy Secretary Chris Huhne told Parliament that the oil exploration so far had been "disappointing," with dry wells and thin yields and massive drilling costs in some of the most storm-swept and forbidding offshore conditions on the planet.

The Argentineans don't believe a word of it. They maintain a special task force of officials from the defense and foreign ministries along with oil and engineering experts who monitor the progress of the four British oil exploration companies at work in the region.

In December, struck by reports of talks between one of these companies, Rockhopper, and the American Anadarko group, the Argentine government launched a diplomatic offensive with its Latin American neighbors to block access for all Falklands shipping to South American ports.

One of the authors of the new report on the potential tax bonanza, Edison's Ian McLelland, said in London, "With current tax and fishing incomes in the region of $40 million, the islands look set to be transformed by the oil industry."

But he added the crucial caveat that with investment of up to $2 billion required to exploit the Falklands oil, the diplomatic risks might prove too high.

"The proverbial spanner in the works that remains is the ongoing political dispute between Britain and Argentina regarding sovereignty of the Falklands," he said.

Britain says its sovereignty over the islands predates the existence of the state of Argentina and it will endure so long as the 3,000 islanders say they wish to remain British.

The Argentines have been raising the diplomatic stakes, accusing Britain at the United Nations of sending the missile-armed nuclear submarine of the Vanguard class to the region to menace Argentina, in defiance of a treaty that seeks to establish a nuclear free zone in the South Atlantic. U.N. Secretary-General Ban Ki-moon called on bother sides to "avoid escalation."

Britain refuses to comment on submarine deployments but denounced the claim as "absurd." And it is true that the British navy's latest warship, HMS Dauntless, claimed to be the most powerful anti-aircraft and anti-missile ship in the world (ironically, it was designed as a result of lessons learned from British losses in the Falklands war) has been deployed to the islands.

Designed with stealth technology to give it the radar profile of a fishing boat, the destroyer's S1850M 3D radar system can track up to 1,000 targets simultaneously and its anti-aircraft Aster missiles can reach out 80 miles -- the Falklands are about 300 miles east of mainland South America-- to swat down attackers. With a crew of 190 sailors and two on-board Lynx helicopters, Dauntless carries Sea Skua and Harpoon anti-ship missiles and top secret anti-missile defenses.

Defense experts warn that British defense cuts mean that the navy couldn't mount another 1982-style counter-invasion against an Argentine occupation of the islands. But the presence of Dauntless, backed up by four advanced Eurofighter Typhoon fighter-bombers from the new Mount Pleasant airfield and some 500 troops, makes it a formidable target for an Argentine attack. Britain sends at estimated $700 million a year to maintain Falklands defenses.

The key question remains how much oil is really exploitable and at what cost. The largest field currently being explored, called Loligo, is claimed to hold 4.7 billion barrels. The field that has been most fully surveyed and developed, Sea Lion, is expected to produce 448 million barrels over the next 20 years, the Rockhopper Explorations company said.

Rockhopper's most recent announcement gave an estimate of 1.3 billion barrels for its Sea Lion discovery, with prospect of more oil in the nearby Caspar and Kermit fields. Other companies, including the Desire group and Falkland Oil and Gas have found dry or disappointing wells and another group, Borders and Southern, has had difficulty hiring a deep-sea drilling rig.

But this dispute is getting beyond economic and engineering logic and the real costs and opportunities of the oil, and is getting embroiled in the same heated rhetoric of national pride and sovereignty that triggered the 1982 war.

Above all, it relates to the new foreign policy posture of the Obama administration and its perceived downgrading of the U.S. commitment to its traditional European allies and to Britain. As the United States focuses more on the Chinese threat across the Pacific and on its own Western hemisphere, the Argentine government suspects that the Brits might be on their own.