According to current and former intelligence officials, the National Security Agency considered abandoning its secret programme to collect and store American calling records in the months before leaker Edward Snowden revealed the practice.
Some officials believed the costs outweighed the programme's counterterrorism benefits.
Even after the leak and the collective surprise around the world, NSA leaders strongly defended the phone records program to Congress and the public, but without disclosing the internal debate.
The behind-the-scenes NSA concerns, which haven't been reported before, could be relevant as Congress decides whether to renew or modify the phone records collection when the law authorizing it expires in June.
