Since World War Two, successive governments have tried to tackle the issue of illegal immigration. Previous attempts to introduce a 'Guest Worker Program' whereby illegal immigrants would be allowed to stay in the US for between three and five years if they were sponsored by a US employer failed. Congress rejected this proposal on two grounds:
As Congress has failed to agree on a plan for managing immigration, some states, e.g. Arizona, have decided to implement their own guest-worker program. However, the US Senate did pass legislation in 2013 that would allow 11 million undocumented (illegal) immigrants the right to stay in the US.
Following the 9/11 terrorist attacks, the US government passed the Patriot Act. This legislation gave US authorities greater powers of arrest, detention and interrogation of suspected terrorists. It has also been used to track down and deport illegal immigrants.
The Patriot Act was renewed by Congress in 2006 before being replaced by the Freedom Act in 2015. The powers of US authorities to arrest, detain and interrogate illegal immigrants remain unchanged by the new Freedom Act.
In 2013 President Obama announced changes to Department of Homeland Security policy that would allow certain undocumented immigrants who were brought to the United States as children the opportunity to apply for a two year stay that would shield them from deportation.
One consequence of this change has been a surge in the number of unaccompanied minors crossing the border hoping to join their parents in the US. Detained children are causing the US authorities a major political problem as they cannot easily be returned to their country of origin.