FISA courts are not sufficient oversight of this stuff. Not to mention there’s little rules for foreign data, including Americans talking to foreigners on the phone. As long as one end is foreign…

You're right. FISA courts are not sufficient oversight. Even Judge James Robertson resigned from the FISA Courts (FISC) in 2005 because:

>On December 20, 2005, Judge James Robertson resigned his position with the court, apparently in protest of the secret surveillance,[11] and later, in the wake of the Snowden leaks of 2013, criticized the court-sanctioned expansion of the scope of government surveillance and its being allowed to craft a secret body of law.[12] The government's apparent circumvention of the court started prior to the increase in court-ordered modifications to warrant requests. In 2011, the Obama administration secretly won permission from the Foreign Intelligence Surveillance Court to reverse restrictions on the National Security Agency's use of intercepted phone calls and e-mails, permitting the agency to search deliberately for Americans' communications in its massive databases.