Border Barriers

A border barrier is a physical structure — a wall, a concrete obstacle, a metal fence, a deep trench or an earthen berm — built by a state at or near an international boundary in order to control or reduce the movement of people, weapons, goods or livestock across it. Where the barrier corresponds instead to a social or political division inside a city or a disputed territory, the term generally used is "separation barrier".

Barriers are not of a single type. Some are military structures arising from war, some are border security installations meant to stop irregular migration or smuggling, and some are hybrids: a physical wall combined with cameras, sensors, unmanned aircraft and data collection. For this reason border researchers usually speak of a "border regime", of which the barrier is one component, rather than of the barrier alone.

Definition and variation in terminology

Naming this subject is itself a political matter. The states doing the building generally use technical terms such as "security fence" or "security barrier", while opposing groups and some researchers use "wall". The term "separation barrier" has likewise been applied to structures that do not lie on an international boundary, such as the lines dividing neighbourhoods in Belfast (Northern Ireland), known there as "peace lines". The distinction between "boundary" and "barrier" matters: not all borders are fenced, and not every barrier follows an official border.

History and the rising number

The fall of the Berlin Wall in 1989 appeared to many to mark the beginning of an era of fewer borders. Published counts show the opposite. Élisabeth Vallet, who has headed the centre for geopolitical studies at the University of Quebec in Montreal, counted some 12–15 border walls worldwide at the end of the Cold War; the number later rose sixfold, to roughly 70 to 74 barriers with a combined length of more than 32,000 km. The increase gathered pace after 2001, and again after 2015 as the number of people arriving in Europe grew.

Within the European Union and the Schengen area, a report produced by the Centre Delàs and published with the Transnational Institute estimated that close to 1,000 km of land walls had been built since the 1990s, adding that electronic systems and maritime assets extend well beyond the physical walls. Oxford-based researchers, drawing on the same data, described the total as close to fourteen barriers around Schengen countries as of 2017.

Well-known examples

Frequently cited examples include: the United States–Mexico barrier; the barrier Israel built in the West Bank; the fence India built on its border with Bangladesh; Saudi Arabia's barrier on the Iraqi border, reported to run about 900 km and to be among the most technologically equipped; the Turkey–Syria barrier; the fence Hungary built on its border with Serbia in 2015; and the earthen berm in Western Sahara. Some of these barriers have not been completed along their full length, existing instead as separate sections along the border.

International law

A border barrier built by a state within its own territory and along a recognised boundary is generally regarded as an exercise of sovereignty. Disputed situations are different. In July 2004 the International Court of Justice (ICJ) issued an advisory opinion holding that Israel's construction of the wall in occupied Palestinian territory, and the associated regime, were contrary to international law, and that obligations followed from this, including halting construction and making reparation. An ICJ advisory opinion is not binding, but it reflects the court's understanding of the law.

Effects and debates

The research reviewed on this subject generally reaches a two-sided conclusion: barriers shift migration routes rather than stopping movement entirely; new and more dangerous routes raise the price charged by smugglers and the risk to life; and the cost of construction and maintenance rises over the long term. On the environmental side, studies of barriers have shown that they cut across wildlife migration routes and affect species that cross the border. On the other side, the states that build them argue that a barrier reduces uncontrolled entry and makes it easier for security forces to manage border movement in an orderly way.