What really bothers me about this is that U.S. companies and individuals have to keep their interactions with the NSA a secret, while obeying whatever demands the NSA has, including the installing of back-doors.

Trust is a fragile thing and we rely on trust for conducting business and for living our lives. My trust in U.S.-based companies has been shaken. Even if the affected companies (such as Google, Microsoft, Apple) want to be trustworthy for their customers, they can be coerced by law to obey whatever the NSA demands and they must also keep it a secret, with absolutely no transparency - they aren't even allowed to say "yes, the NSA demanded some things and we unfortunately complied". Even worse, they can be coerced into making public statements that are full of lies.

I can no longer trust any U.S. based company again.

For example, right now I'm using Skype. But what if the Skype client has a backdoor allowing one to open and listen to my mike any time they want (it's a proprietary blob, we'll never know). What if this backdoor gets hacked and used by people that are not part of the U.S. government? So in spite of the best intentions of the people working on Skype and the NSA; even if I've got "nothing to hide", Skype is all of a sudden a security liability and nothing (short of an open-source client that I can compile and run) can prove otherwise, because Microsoft isn't allowed to be open about it. And I can no longer rely on the fragile trust I've had for Microsoft, because Microsoft can be coerced into being untrustworthy.

See how it goes? We'll see how this unfolds over the next years, however the damage done to U.S. companies will prove to be massive.