Justifying the secret surveillance program, a top US official has said that America neither uses its intelligence capabilities to collect trade secrets of foreign companies, nor does it listens to everything said by every citizen of any country.
"We do not use our foreign intelligence collection capabilities to steal the trade secrets of foreign companies in order to give American companies a competitive advantage," Robert Litt, the top lawyer for the Office of the Director of National Intelligence said.
Litt said that US did not indiscriminately sweep up and store the contents of the communications of Americans, or of the citizenry of any country.
"We do not use our intelligence collection for the purpose of repressing the citizens of any country because of their political, religious or other beliefs," he said.
Delivering his speech in the wake of the disclosures about two programs that collect foreign intelligence: the bulk collection of telephony metadata, and the so-called "PRISM" program, Litt asserted that programs are not illegal.
"These programs are not illegal. They are authorised by Congress and are carefully overseen by the Congressional intelligence and judiciary committees. They are conducted with the approval of the Foreign Intelligence Surveillance Court and under its supervision," he said.
Litt said that US collected metadata-information about communications-more broadly than the actual content of communications as it was less intrusive than collecting content and helped it to focus on appropriate targets.
"But it simply is not true that the United States Government is listening to everything said by every citizen of any country," Litt said.
"I believe that our approach to achieving both security and privacy is effective and appropriate. It has been reviewed and approved by all three branches of Government as consistent with the law and the Constitution," he said.
Litt said that even before the recent disclosures, president Obama had welcomed a discussion about privacy and national security.
All three branches of government had known about the programs, approved them, and helped to ensure that they complied with the law, Litt said, adding that only time would tell the full extent of the damage caused by their unlawful disclosures.
"Information that can help us identify and prevent terrorist attacks or other threats to our security is often hiding in plain sight among the vast amounts of information flowing around the globe," he said.
Noting that the business of foreign intelligence has always been fundamentally different from the business of criminal investigation, he said rather than attempting to solve crimes that had happened already, the US was trying to find out what was going to happen before that happens.
"We may have only fragmentary information about someone who is plotting a terrorist attack, and need to find him and stop him," he said.
