Quoting Edward Snowden

" I believe that suspicionless surveillance not only fails to make us safe, but it actually makes us less safe.  By squandering precious, limited resources on "collecting it all," we end up with more analysts trying to make sense of harmless political dissent and fewer investigators running down real leads.  I believe investing in mass surveillance at the expense of traditional, proven methods can cost lives, and history has shown my concerns are justified."

- Edward Snowden

Source: Edward Snowden testimony (PDF) to the European Parliament