The fundamental goal of the ad-supported web is to collect and capitalize on data from its users; rather unsurprisingly, that data is just as valuable to the government as it is to Facebook and Google. You may think you’d never willingly provide the FBI or NSA with a map of your entire private life, but, in fact, you probably already have.

Tonight’s episode of PBS’s FRONTLINE, “United States of Secrets: Privacy Lost,” is the second of a two-part series on government surveillance. The first, produced by League of Denial’s Michael Kirk, deals with the post-9/11 political climate that empowered the NSA to begin the bulk collection of data on millions of Americans.

Part two, from journalist Martin Smith (To Catch a Trader, Money, Power & Wall Street), focuses on Silicon Valley’s complex relationship with the NSA.

In the documentary, privacy expert Chris Hoofnagle explains, “These companies are in a very difficult spot, because the types of activities they engage in are very similar to surveillance. It is surveillance, just for advertising, rather than for law enforcement.”

So, the crux of the problem is this:

For companies like Google and Facebook, it is a core requirement of their businesses that you be willing and able to share data about yourself. Unfortunately for Silicon Valley and, by extension, everyone else, it is difficult, if not impossible, to prevent the NSA from piggybacking and gathering the data that you generate through the use these products.

According to documents leaked by Edward Snowden and investigated by Barton Gellman of the Washington Post, the intelligence community has become extremely effective at grabbing data from companies without their cooperation, or even their knowledge.

FRONTLINE highlights several examples of this, including a program where the NSA not only tapped the actual fiber-optic cables that Google uses to transmit information between data centers, but one that surreptitiously gathers Google’s tracking cookie information from internet traffic and uses it to track individual users across the net. Google, which chose not to participate in the documentary, is presented as having had no idea that the NSA was even capable of doing this, or that the code in question could be used this way.

So, should you be helping Facebook and Google to generate this data in the first place? Is it worth it? That’s the question that Silicon Valley hopes you won’t ask.

The second part of United States of Secrets: Privacy Lost, airs tonight at 10pm ET on your local PBS station and online.

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