Ever since whistleblower Mark Klein revealed that he’d build a secret wiretapping room for the NSA at AT&T’s San Francisco switching center, we’ve known that the NSA was illegally wiretapping the Internet’s backbone. But the government has steadfastly denied it. However, as Bruce Schneier documents, Senator Diane Feinstein has let slip that the NSA is tapping the backbone on several occasions, though president Obama continues to deny it.