The world's attention is turning to the waters off the coast of Australia, where some 400 asylum seekers are waiting to learn their fate. The group, who appear to be mostly refugees from the tyrannical Taliban regime in Afghanistan, were rescued last Sunday by a Norwegian freighter when the wooden Indonesian vessel that carried them issued a distress call. Indonesia would not accept the refugees, and so far Australia is keeping them at bay as off its northwest shore, near Christmas Island.

To turn desperate people away at a place named Christmas Island may seem particularly callous. But Australian Prime Minister John Howard made a valid point when he spoke of "the right of Australia to control who comes to this country." Indeed, the definition of sovereignty is effective control over who is allowed to enter a country's territory. Unless a government has the military and police power to defend its borders from hostile invasions or peaceful migrations, it is sovereign only in theory, not in fact.

But don't states have a "humanitarian" duty to use their power to help unfortunate people beyond their borders? Indeed they do -- but only up to a point.

A government is not a church and it is not a charity. It is more like a bank. Bankers may feel sorry for beggars they encounter in the street, but they would violate their fiduciary duties if they took the money that their customers have deposited with them and gave it away on the basis of their personal sentiments. Statesmen must be guided by their heads and the national interest, not by their hearts and their personal feelings.

And the national interest, even of a country that permits humanitarian refugees to camp on its territory, requires the country to treat the acceptance of refugees as an exceptional situation, not the rule. Otherwise a country that is too generous will become a welfare magnet -- attracting an ever-escalating number of refugees who, after fleeing their homelands, are rebuffed when they try to enter countries with stricter policies toward unwanted immigration.

Once admitted, the host country cannot permit refugees to starve or suffer from illness. An offer of temporary shelter can easily turn into permanent dependency on the host government -- that is, on the hard-working citizens who pay taxes chiefly for the benefit of themselves and their families, not for the benefit of foreigners with whom they may have little or no connection other than sympathy.

Just as it is ethical and necessary for statesmen to put the national interest above unthinking humanitarianism, so it is both ethical and necessary for individual citizens to put the interests of their families, neighbors and fellow nationals above the interests of outsiders. Each of us is at the center of a series of concentric circles ranging from ourselves and our families to humanity at large. As the circles grow larger and people become more distant from us, our moral duties to them remain real but become weaker and weaker.

In the ethical tradition of the Catholic Church, whose very name is a synonym for "universal church," there is even a name for this commonsensical theory of concentric morality: "ordinate charity." The idea is simple. The best way for the world to be improved is for everyone to help those who are nearest first.

Ordinate charity makes sense for two reasons. First, you are likely to be better informed about people and situations in your own neighborhood, and your own country, than about those in remote lands. You are therefore less likely to accidentally harm those whom you are trying to help as a result of ignorance.

In addition, you are more likely to be effective, the closer you are to home. People other than tycoons or pop stars find it much easier to help unfortunate fellow citizens down the street or across town than to help suffering people on the other side of the world.

Nothing here means that there is no leeway for humanitarian aid. What it does mean is that humanitarian aid becomes compelling only when we have already satisfied the demands of the national interest -- and also have resources and energy left over after we have aided our neediest neighbors.

Recently more than 100,000 refugees each year have been admitted or have applied for asylum while in the United States -- most of them from a few countries, including the former Soviet Union, Bosnia, Kosovo, Vietnam, Somalia, Sudan, Cuba and Iraq. American statesmen have a moral duty to help the victims of genocide and famine, but at the same time they have a duty to spend the limited dollars of our limited government on needy Americans and America's needs.

The United States has only around 4 percent of the world's population and accounts for about a fifth of the world's economic activity. Some of our surplus can and should be spent on international charity -- as long as we remember that charity begins at home.

The refugees aboard Tampa will find temporary homes somewhere in the next few weeks or months, and we must hope that they will be able to return at some point to an Afghanistan that is freer and more prosperous than the one that they have fled. In their wake, however, the debate about the duty of nations to refugees, and the limits on that duty, will continue.