When Argentina invaded the Falklands in April 1982, it came as a shock to most of Whitehall. With communications to the islands disrupted, for several excruciating hours Margaret Thatcher's government, then not known for its competence, was unable to confirm if the islands had actually been captured.
Thirty years on, tensions between Britain and Argentina over the islands have been building up much more steadily, publicly and self-consciously.
In 2007, significantly also a Falklands war anniversary, on the 25th anniversary, Argentina officially reasserted its longstanding claim to the islands after an extended postwar silence.
The same year, Britain announced its intention to claim a vast stretch of the south Atlantic seabed around the islands via the UN. In 2010, after British-based oil companies began to show a firm interest in the seabed, Argentina decreed that ships passing through its waters to the islands would require permits.
This sporadic diplomatic and commercial tit-for-tat has recently acquired more momentum. Last September, the Argentinian president, Cristina Fernández de Kirchner, said at the UN that Buenos Aires might ban the only weekly commercial flight to the Falklands from flying through its airspace.
In December, Argentina persuaded neighbouring countries, including Chile – Britain's one, crucial ally in the region during the war – to ban civilian ships flying the Falklands flag from entering their ports. Last month, David Cameron provocatively accused Argentina of "colonialism" in continuing to claim the islands despite their inhabitants' wish to remain British.
On Tuesday, Britain announced the imminent deployment of the destroyer HMS Dauntless to the south Atlantic, replacing a less powerful warship, and Prince William is due to begin his long-trailed Falklands posting, arriving in "the uniform of the conqueror", to use Argentina's theatrically disapproving phrase.
For the 3,000 Falklanders, all this manoeuvring has brought higher food prices and a growing sense of encirclement. But for the other interested parties, the ongoing dispute has benefits. British military figures opposed to the current defence cuts have made the renewed threat to the Falklands their cause.
Bellicose British journalists have a new potential war. Fernández has worldwide publicity for her country's claim, and Cameron has an opportunity for flag-waving to distract from a misfiring economic policy – just as Thatcher did in 1982. Yet it is much harder, for now at least, to see the situation ending in war. Fernández is scathing about the 1982 invasion and says she merely wants Britain and Argentina to talk.
The British garrison in the Falklands is more than 10 times bigger than it was in 1982. Most likely, after the anniversary season passes, the Falklands will quietly recede as a news story until the next big commemoration – or there is a big oil find.