How many terrorist attacks were thwarted by the phone call surveillance program in the USA (implemented as part of PRISM)?

The article discusses issues related to the illegal and costly phone surveillance conducted by the NSA. The owner of Tutanota, a well-known email encryption service, points out the flaws in the surveillance system. The authors highlight that in many countries, including the United States, mass data collection programs are often undertaken without proper safeguards. This type of surveillance not only infringes on citizens' privacy but also consumes enormous financial resources that could be redirected to other purposes. The topic is especially critical given the increasing threats posed by the technology we live in. It reminds us of the importance of maintaining a balance between security and the costs we incur to achieve it.