Troubles at the U. S. border with Mexico have plagued the last three American administrations. Georgia, like the rest of the country, has had to grapple with the consequences of that plague. Federal, State, and charitable organizations work to enforce migration law while at the same time providing humanitarian assistance to migrants, even those here illegally. Sympathy for migrants is understandable and in Georgia alone has meant that federal and state authorities and charitable organizations have spent an estimated hundreds of millions of dollars in time, energy, and resources to help them. It is an expensive problem that is not going away, which makes “the border” a hot issue in American politics.

What does that phrase, the border, actually mean? In its most basic sense, a country’s border establishes the limit of its sovereign territory with each country controlling its border according to its own needs for safety and security. It may seem that a border can be a simple barrier to prevent unauthorized movement of people, material, or products from one country to another. In reality, a functioning border has to be a complex arrangement that will bar illegal cross-border traffic while simultaneously and efficiently allowing legal movement with a variety of shades ranging from tourism and commerce to education and asylum.

Border control is best achieved by a partnership between the two countries sharing a common border. Implicit in that work is every country’s obligation to do no harm to its neighbor and to not allow others to do that harm from its territory. For example, it violates international law for one country simply to invade another. It is equally illegal for that country to allow others to attack its neighbor from its territory. Both cases violate the do no harm rule.

Examples of such violations are not rare. Decades ago, Cambodia and Laos allowed North Vietnam to use their territory for its attacks on South Vietnam. Those were violations of the do no harm obligation. Today, Lebanon allows an armed organization, Hezbollah, to attack its neighbor, Israel, from within its territory. That’s a violation of the do no harm standard. Violations invite retaliation thus causing one problem to build upon another.

While less dramatic than armed attack, countries that do nothing substantial to prevent the illegal movement of people, weapons, or drugs from their sovereign territory into a neighbor’s territory also violate the do no harm obligation. Mexico, pro forma a friendly neighbor, is in many ways a failed state. One expression of its failure is its inability to control its borders. Its own southern border is virtually open to illegal migrants and drugs from other failed states, mostly in Latin America, but also from countries around the world. Those migrants and drugs move north to the U. S.-Mexico border with little resistance from Mexican authorities and, once at the U. S. border, they are allowed to enter the U. S. without substantive impedance. That is a violation of the do no harm standard.

The failure of Mexico as a border partner strains the U. S.’s ability to block illegal migration of people and goods while simultaneously allowing for efficient legal movement. For that reason, American border and immigration services need expansion to meet current need. America needs a healthy rate of legal migration, but that rate has to be regulated not only for security but for the country’s capacity to assimilate migrants in a fair and reasonable manner. America’s relative prosperity and standards of law are a beacon to many, but the country cannot be expected to be an unregulated escape valve for every failed state south of the Rio Grande and east of Suez.