The NSA (and the similar agencies in other countries) can take advantage of the proliferation of new technologies. Back when people wrote letters they needed to physically open them and copy the contents. Now with computers and email it can be done automatically.It used to be that each house had one phone and ‘taping’ the line was a complicated operation. Now we all have mobile phones and they are easy to compromise, it can be done automatically.
You really thought that the NSA had a budget of several billion dollars and tens of thousands of personnel in order to spy on a few goat herders in Afghanistan?
Can you protect yourself with encryption? We already know that NSA technicians worked with Microsoft in order to make Windows more ‘secure’ and it seems reasonable to assume that they have a similar relationship with Intel. So both PC hardware and software is compromised at the source. We also know that the largest internet companies work with them...
In the end all this information gives the NSA (and similar agencies) the opportunity to become a Super-Gestapo. What can a person do to prevent this? I simply don’t know.