We’ve had these laws since the late 1970s

Privacy of phone records? Surveillance of foreign agents inside the U.S.? We've had the laws on the books for some time. What we've learned in the current Obama scandals is we can't trust government agencies not to misuse the guarantees. It’s disturbing that opinions on the law change among the electorate depending on who is in power.

Smith v. Maryland, 442 U.S. 735 (1979) was a case in which the Supreme Court of the United States held that the installation and use of the pen register was not a "search" within the meaning of the Fourth Amendment, and hence no warrant was required. The pen register was installed on telephone company property at the telephone company's central offices. In the Majority opinion, Justice Blackmun rejected the idea that the installation and use of a pen registry constitutes a violation of the "legitimate expectation of privacy" since the numbers would be available to and recorded by the phone company anyway. [Wikipedia]

The United States Foreign Intelligence Surveillance Court (FISA court, AKA FISC) is a U.S. federal court authorized under 50 U.S.C. § 1803, Pub.L. 95–511, 92 Stat. 1788, enacted October 25, 1978. It was established by the Foreign Intelligence Surveillance Act of 1978 (FISA). The court oversees requests for surveillance warrants against suspected foreign intelligence agents inside the United States by federal law enforcement agencies (primarily National Security Agency and the F.B.I.). FISA and its court were inspired by the recommendations of the Church Committee. . . It is also rare for FISA warrant requests to be turned down by the court. [Wikipedia