Today there are more than 1 billion regional and international migrants, and the number continues to rise: within 40 years, it might double due to climate change. While many of these migrants might not cross a regional or international border, people change residences and jobs more often, while commuting longer and farther to work. This increase in human mobility and expulsion affects us all. It should be recognised as a defining feature of our epoch: the 21st century will be the century of the migrant.
In order to manage and control this mobility, the world is becoming ever more bordered. In just the past 20 years, but particularly since the terrorist attacks of 11 September 2001 on the US, hundreds of new borders have emerged around the world: miles of new razor-wire fences and concrete security walls, numerous offshore detention centres, biometric passport databases, and security checkpoints in schools, airports and along various roadways across the world. All attest to the present preoccupation with controlling social motion through borders.