Would you prefer that the government watches your Google searches, your forum postings, your Facebook messages, and your emails and potentially stops these terrorist attacks, or would you prefer to be free of government spying and possibly give up safety?
If another Boston Bombing happened and it was later found out that the terrorists had bought pressure cookers, nails, and other bomb-making materials on Amazon, wouldn't there be outrage that it didn't raise any red flags? Yet when the government tries to investigate potential threats like the one explained in the article, they're seen as bad guys.
I think the real problem is that we were never asked. 9/11 happened and the war on terror began. Americans never chose to be spied on in order to prevent attacks, it was just assumed that we valued our safety more than our privacy.
So when I read about NSA spying articles, or blog posts like this, I always have to ask myself "what if these really were terrorists?" because I know that there are hundreds or even thousands of lives saved through operations like this, and we never hear about the successes.