This week marks the 40th anniversary of the Argentine invasion of the Falkland Islands (Islas Malvinas), sparking the beginning of a three-month long war with Great Britain. At a time when Europe is at risk of military conflict with Russia over Ukraine it is worth looking back at the lessons we can draw from this 40-year-old conflict.

First and foremost, what the Falklands can teach us is that military conflicts can legitimize tough, unpopular, policies at home. Second, conflicts like this one are motivated in part, if not principally, by a country’s international decline. Such concerns about status ironically lead to more pugilistic policies, which only serve to exacerbate that decline.

The Falkland Islands, a few hundred miles off the coast of Argentina in the South Atlantic, have been claimed by Britain since 1833. Home to around 1,800 islanders at the time of the invasion, the islands were not a strategic priority for Britain.

Indeed, prior to the Argentine invasion on April 2,1982, Prime Minister Margaret Thatcher’s government was negotiating a “lease-back” of the islands to Argentina. However, the islands were more important to the Argentines, who made longstanding claims over them. The military junta, led by General Leopoldo Galtieri, believed that seizing the islands would offer the regime support at home, rallying the people of Argentina around their flag and the regime during a tumultuous time. The invasion was supposed to be quick. The junta believed that victory would come fast, and that Thatcher would not respond. 

However, after Argentina invaded, Thatcher sent a task force to the South Atlantic to retake the islands. The war was brutal and a logistical challenge for the British, who had to engage the Argentine military 8,000 miles from home. The conflict cost the lives of 255 British and 649 Argentines over the course of a few months. Over 2,000 British and Argentines were wounded. The war cost Britain $1.19 billion in 1982 dollars. But despite all of this, the British took back control of the Falklands and in the process, shored up Britain’s commitment to the islands, which remains today.

But the conflict in the Falklands marked a turning point for Thatcher, one that would have longstanding domestic and foreign policy consequences.

Beyond the costs in blood and treasure, there were domestic implications, too. The conservative prime minister linked victory in the South Atlantic and domestic struggles at home together to claim newfound confidence, capitalizing and exploiting Britain’s successful military campaign to rally domestic support for her political agenda, including unpopular anti-inflationary measures, trade union reform, and cuts to social spending. 

The “Iron Lady” further linked domestic political problems, such as the railway strikes, or NHS pay disputes, to the Falklands. If only those troublesome Brits who engaged in labor disputes and calls for better pay would realize the sacrifices that were needed to bring Britain back from the brink, if only they would take lessons from those who fought in the Falklands, then Britain would find her way again. 

For Thatcher, the Falklands war showed that “Britain has not changed and that this nation still has those sterling qualities which shine through our history.” Her political power grew immensely, aided in part by the British media infamously engaging in jingoistic and militaristic headlines. “Gotcha: our lads sink gunboat and hole cruiser,” the Sun newspaper gleefully celebrated, while the Daily Mail celebrated the “Death of the Belgrano.” 

Victory in the Falklands — what Thatcher called “the Falklands factor” — represented the best of Britain, a Britain that “had no illusions about the difficulties” of the tasks at hand, a Britain that had “re-kindled that spirit which fired her for generations past and which today has begun to burn as brightly as before.” In this way of thinking, the Falklands war was not just a story of Britain claiming a victory in the South Atlantic, it was a story of the beginning of Britain’s renewal at home.

The prime minister’s preoccupation with Britain as a declining power shaped the response to the conflict. Scholars have persuasively counseledretrenchment when a nation is in decline. After the invasion of the Falklands by Argentina, Thatcher and the UK Government did the opposite. The Argentine invasion was seen by many as a slap on the face, of a sign of Britain’s inability to deter adversaries and part and parcel of Britain’s decline internationally. 

For example, Conservative MP Alan Clark said in his diary at the time of the invasion that “we’re a Third World Country, no good for anything.” Clark’s views were echoed in public sentiment. Early in the crisis, polling showed that 50 percent of the British public thought that the crisis had worsened Britain’s standing in the world. By the end of May 1982, however, 38 percent of Brits believed that world opinion of Britain had improved, 34 said it remained the same, and only 19 percent thought it had gone down, according to a MORI poll. 

Clark would go on after victory in the Falklands to view the consequences of the conflict through the prism of Britain’s major power status. Victory in the Falklands, he said, “enormously increased our world standing…I mean bugger world opinion—but our standing in the world has been totally altered by this.” The Times of London argued that the reason for reestablishing the Falkland Islands had been “to re-establish the evidence of British willpower, because the whole structure of this country’s standing in the world, her credibility as an ally, as a guarantor of guarantees, as a protector of her citizens.”

In a key speech to Conservatives in Cheltenham shortly after the end of hostilities in July of 1982, Thatcher claimed that Britain had “ceased to be a nation in retreat.” 

“We have instead a new-found confidence — born in the economic battles at home and tested and found true 8,000 miles away. That confidence comes from the re-discovery of ourselves, and grows with the recovery of our self-respect. And so today, we can rejoice at our success in the Falklands and take pride in the achievement of the men and women of our Task Force. But we do so, not as at some last flickering of a flame which must soon be dead. No — we rejoice that Britain has re-kindled that spirit which has fired her for generations past and which today has begun to burn as brightly as before. Britain found herself again in the South Atlantic and will not look back from the victory she has won.” 

Britain, at least to many, was back.

Forty years on, the Falklands war reminds us that conflicts have immense costs not only in blood and treasure, but can have a huge impact on domestic politics at home. The war in the Falklands could have been a lesson for restraint but instead emboldened a dangerous precedent at home: Britain “was back” and there was no need to pull back from costly commitments abroad.

Victory in the South Atlantic left Britain feeling like the great power Thatcher thought that it should be. This enduring sense of major power status — at least in part — led to Britain’s calamitous involvement in Iraq and Libya. Delusions of grandeur can be dangerous too.