Under a post-9/11 surveillance program known as "Upstream", the NSA is systematically searching Americans' internet communications as they enter and leave the United States. The agency sifts through these streams of data looking for "identifiers" associated with its many thousands of foreign targets identifiers like email addresses and phone numbers. The NSA does all of this without warrants, without any individual judicial approval, and without showing that any of the people it is surveilling " including countless Americans " have done anything wrong. This surveillance raises serious constitutional concerns, but no court has ever considered a legal challenge to it because the government has claimed that allowing a suit against Upstream surveillance to go forward would implicate "state secrets". In 2007, for example, an appeals court dismissed a lawsuit filed by Khaled El-Masri claiming that, in a case of mistaken identity, he had been kidnapped and tortured by the CIA. The court acknowledged the public evidence of El-Masri's mistreatment but held that state secrets were too central to the case to allow it to go forward. And in 2010, a different appeals court dismissed a lawsuit filed by five individuals who claimed that one of Boeing's subsidiary companies had flown the planes carrying them to the black sites where they were tortured by the CIA. This use of the state secrets privilege " to dismiss cases " departs from the supreme court's narrow framing of the privilege.