Good old Uncle Sam

 

It would be extraordinarily difficult for anyone but a government agency (or a phone company insider) to open up a reliable digital tap on your line. Aside from the occasional complete loss of spine and dignity when faced with a government demand, phone companies and ISPs protect their customer records fiercely.

Nearly every presidential administration since the late 1800s has spied on people using wiretaps. Clinton did it, both Bushes did it, and Obama is probably doing it. Listening in on phone conversations, just like reading the mail, is a core competency of the United States government.