Next week, Falkland Islanders will go to the polls to answer a momentous question: “Do you wish the Falkland Islands to retain their current political status as an Overseas Territory of the United Kingdom?”

It will be a classic exercise of a people’s right to self-determination. So you would expect the U.S. to back this referendum to the hilt. Sadly, you’d be wrong. As Secretary of State John F. Kerry made clear in London last week, the islanders’ majority voice will fall on deaf ears in Washington.

There is little doubt that the islanders will vote, by an overwhelming majority, to retain their affiliation with the United Kingdom. Culturally, linguistically and historically, the islanders are British. When the British first landed there in 1690, they found no indigenous population. Some of today’s residents can trace their roots on the islands back to the 1830s, when Britons established a permanent settlement there.

Yet Argentina has coveted the islands for years. Neither history, international law nor the wishes of the islands’ inhabitants support Argentina’s claim. But Argentina has fallen on hard times. Perhaps to distract the public from economic woes, Argentine President Cristina Fernandez has been beating the drum about the Falklands.

To help settle the issue, the Falkland Islands government proposed a referendum, and the British government has been completely supportive. London has made it clear that it will respect the outcome of the referendum no matter how the islanders vote.

Argentina is having none of it. Rather, Buenos Aires has embarked on a campaign to dehumanize the islands’ inhabitants. Argentine officials describe the Falkland Islanders as “a population and not a people.” The foreign minister recently declared: “The Falklands Islanders do not exist. What exist are British citizens who live in the Islas Malvinas [the Falklands].” The Argentines are the ones using the language of colonizers.

Ms. Fernandez has backed her administration’s dehumanizing rhetoric with a campaign of intimidation against the islanders. Her navy has boarded Falkland fishing boats and blocked civilian cruise liners from entering Argentine ports if they have first visited the Falkland Islands.

Why should the U.S. care? Well, in addition to caring greatly about the universal right to self-determination — a key principle on which our nation was founded — we should care because the situation involves our No. 1 ally, the United Kingdom.

Yet, instead of backing our best friend, the Obama administration has sided with Argentina by supporting its calls for a negotiated “settlement” over the islands. Worse, the State Department has refused to say that it will recognize the outcome of the upcoming referendum.

Of course, neither the Falkland Islanders nor the U.K. needs Uncle Sam’s support for the referendum to be a success. But wouldn’t it be nice if America stuck up for its allies? All the Falkland Islanders are asking for is recognition of their right to self-determination — a right guaranteed by the United Nations Charter and the International Covenant on Civil and Political Rights. It is embarrassing to think that the leader of the free world would not back such a fundamental right.

The administration has placed the U.S. on the wrong side of history. At the end of the day, it is not about the islands themselves, but the people living there. The Falkland Islanders should have the right to choose their own future. If President Obama cannot bring himself to support the islanders’ right to self-determination and instead continues to back Argentine calls for negotiations, then his administration has some soul-searching to do.

The war fought and won by Britain in 1982 to expel the Argentine invaders was a victory for self-determination. Margaret Thatcher showed the world that British sovereignty would not be trampled and that she would do whatever it took to liberate the occupied islands. Today, this commitment to self-determination is manifesting itself in next week’s referendum. The Falkland Islanders have been given a voice. Mr. Obama must listen.

-Luke Coffey is the Margaret Thatcher fellow at the Heritage Foundation’s Margaret Thatcher Center for Freedom.