Most of the private data Google collects about individuals is provided freely by the people. (Perhaps not all, and maybe that should change, but the point still stands.) Google and others use it to target advertising. The government uses it to monitor people for perceived wrongdoing and imprison them. There's a difference.

Privacy isn't necessarily about keeping everything private from everyone, it's also about choosing who you reveal information to. It is perfectly legitimate to be willing to reveal private information to Google, but wishing to prevent the government from being able to warrantlessly scoop it up as well.

It bears repeating: "The problem isn't so much that we haven't set up a legal architecture to preserve our online privacy from the government; it's that we haven't set up a legal architecture to preserve our online privacy from anyone at all. If we don't have laws and regulations that create meaningful zones of online privacy from corporations, the attempt to create online privacy from the government will be an absurdity."

There's also the perverse result that government has little incentive to pass laws protecting personal privacy from corporations.