Weeks after the September 11 attacks , U.S. President George W. Bush signed the Patriot Act to ensure no disruption in the government 's ability to conduct global surveillance : The Patriot Act was extended by U.S. President Barack Obama in May 2011 to further extend the federal government 's legal authority to conduct additional forms of surveillance such as roving wiretaps
September 11 attacks
September 11 attacks
Global surveillance