I'd rather them spy on my internet history than have my sister/daughter/niece become a sexual assault victim.
The NSA has no role whatsoever in on-line perverts/predators. Your local police will handle that, in some cases the FBI may get involved. They will follow the law and get a court order to retrieve the suspects computer, & the ISP & phone company data. Its up to the computer users to have a bit of street or more like on-line smarts, kids need to be taught at home what they are not permitted to do. Crime has not dropped after the NSA spying. The best & really the only defense is to teach the vulnerable on what is dangerous in the web world. If they are to young/old to comprehend pull the plug.
The highest courts in the U.S. ruled that the NSA spying as illegal/unconstitutional. Having grown up in a free country I not only value but demand my freedom & privacy. The most oppressive regimes of all times will envy the NSA's dragnet/surveillance state - like North Korea or Berlin in post WW2 under the Stasi.
“Those who surrender freedom for security will not have, nor do they deserve, either one.” Ben Franklin
P.S. Since you're clearly correct.
The NSA alerts local officials.