<human>:  Where do the NSA and other National Security agencies get the authority to spy on Americans?
<bot>: They get the authority to spy on Americans from the USA Patriot Act. The Patriot Act was passed in 2001, and it gives the government the authority to collect intelligence information on any person suspected of being a terrorist. It also allows the government to collect intelligence information on any person who has been involved in any way with terrorism, and it allows the government to collect intelligence information on any person who is considered to be a threat to national security.