Who are you calling colonialists?

Are the islands rightfully Argentinian, then? The answer depends on how much history you can swallow, your views on colonialism versus self-determination, and the value you place on an estimated 60 billion barrels of oil. When the Argentine writer Jorge Luis Borges dismissed the 1982 Falklands war between his country and Britain as "two bald men fighting over a comb", that vast reservoir of wealth had not been discovered.

Last week, Cristina Fernandez de Kirchner, Argentina's president, dispatched a furious letter to David Cameron via adverts in London newspapers and once again demanded the return of her country's comb. She made no mention of oil. Instead, she invoked the 180th anniversary of the day – January 3, 1833 – Argentina was "forcibly stripped of the Malvinas Islands" in "a blatant exercise of 19th-century colonialism". It was rousing stuff.

Some of us said much the same things just over 30 years ago when Margaret Thatcher was sailing her task force over those thousands of miles of ocean. My own view, no doubt cynical, was that either Britain would be rid of a foul prime minister thanks to the affair, or Argentina would be shot of a disgusting military junta. Either way, someone, poor squaddies aside, would be better off. But the notion that the UK had some inalienable right to an island group on the other side of the world was laughable.

Those of us who took that view would later argue, like armchair diplomats, for a shared jurisdiction between Britain and Argentina, if only to keep the islanders happy. We didn't pause to ask if those such as Kirchner and her compatriots had any legitimate say in the matter. We knew about Britain's imperial history, and every "blatant exercise" of colonial power. Whoever was entitled to control the Falklands, it couldn't possibly be the UK. But what right did Argentina possess?

The history is messy. Many countries have stuck their flags in the islands since the 17th century. Spain, Portugal, France and Britain all played the usual games when the Falklands contained little worth fighting over save dried fish. Kirchner can argue, correctly, that her people were kicked out – or "invited to leave" – in 1833. But then, a British sea captain had already made the flag-planting claim on behalf of George III in 1765. More to the point, the Republic of Argentina did not come into being until 1853. You can take your pick.

It remains a fact that the Falklands are beyond Argentinian maritime boundaries. The islands are also outwith Argentina's "exclusive economic zone" – effectively its 200-mile limit – though Buenos Aires has attempted to stretch the concept. The existence of a British Overseas Territory such as the Falklands might be an absurd relic of empire. But what is Kirchner really saying? That Argentina wants its colony back? The President hardly helps her anti-imperialist argument, in any case, when she asserts that it doesn't matter what the islanders think, feel, or say.

They will hold a referendum on sovereignty in March. Cameron believes this is a splendid idea, unlike a certain other plebiscite on relations with Britain. Nor is the Prime Minister quibbling with the Falklands over the wording, which is probably just as well. At six paragraphs and 146 words, "the question" is loaded to the gunnels before it gets around to asking: "Do you wish the Falkland Islands to retain their current political status as an Overseas Territory of the United Kingdom?"

Cameron can afford to be sanguine. The outcome is not in serious doubt and this is, or should be, a problem for Argentina. The rhetoric of anti- colonialism always plays well in America Latina, for the very good reason that the great powers visited misery and staggering exploitation on the region until its people began to break free. But how is that fact to be balanced against the right to self-determination? The ancestors of the islanders might have been "implanted", as Kirchner puts it, but is a tiny community therefore deprived of democratic rights after 180 years?

The first oil should emerge from the seabed around the Falklands in 2017. Argentina has announced that it, too, will begin to explore for black gold in the near future. Neither London nor Buenos Aires allows such facts to spoil the rhetoric over democratic rights and wrongs, but neither is under any illusion: trillions are at stake. Or are 2841 individuals to be allowed to keep the lot?

The islanders will at least have their referendum. The penguins and elephant seals of Antarctica have no such luxury. Uncounted numbers of them recently became residents of Queen Elizabeth Land when the Foreign Office decided to rename a swathe of their home – just twice the size of the UK – as a Jubilee gift to the monarch. Once again, Argentina was furious.

Britain's ambassador to Buenos Aires was called in and handed one of those stiff notes popular in diplomatic circles. The UK stood accused of "anachronistic imperialist ambitions that hark back to ancient practices". Argentina would refuse to recognise the existence of Queen Elizabeth Land. But since when, you might ask, was a pie-shaped slice of the Earth's frozen backside sovereign Argentine territory?

As it turned out, the staunch anti-colonialists have simply stuck a flag into Antarctica, as have Britain, France, Australia, New Zealand, Chile and Norway. No other countries on Earth recognise these claims, though the UK calls its holding another of our "overseas territories". We are, meanwhile, in dispute with Chile and Argentina, and have been since the 1950s, over who has a right to what. Hence the accusation of "anachronistic imperialist ambitions" from a government that is 3400 miles away from Antarctica.

London is fully 10,300 miles, if you're wondering, from the icy wastes, but distance is no object when nation states export their hypocrisies. Kirchner's struggling Peronist government faced its first general strike in November after a series of street protests. Inflation is estimated to be running at about 25% (official figures are derided) and allegations of official corruption are mounting. Taking out an advert in the London press to abuse Cameron over Las Malvinas is an act of desperation, not defiance.

It suits Cameron perfectly well, no doubt. Here is a precious chance to seem Thatcherite, or at least to sound like a democrat. What would Britain under his leadership not do for a plucky far-flung island group in (entirely imaginary) peril?

The UK has 1200 troops, four Typhoon Eurofighter aircraft, Rapier anti-air missiles, a guided missile destroyer, and (though hush-hush) a Trafalgar-class nuclear submarine hanging around the Falklands.

In 2006, that lot was costing us £143 million a year until the MoD neatly omitted wages, equipment and other sundries from the bill.

Still, for fewer than 2900 people in a place where Britain has no right to be, it's a lot. To protect 60 billion barrels of oil, it's a bare minimum.