Security vs. privacy: Evaluating the government’s case

President Obama recently told Americans that we have to give up some privacy in the name of security. Is the government’s demand reasonable?
Last month, I took up the issue of privacy from the perspective of the end user. This time I will try to shed some light on the government’s position, to see if it’s reasonable.
From the advent of telecommunications systems, the government has maintained the ability to tap calls and collect our communications. However, thanks to the Fourt