PRIVACY: Does information's availability justify its use?

Governments collect massive amounts of data on individuals and organizations and use it for a variety of purposes: national security, accurate tax collection, demographics, international geopolitical strategic analysis, etc. Corporations do the same for commercial reasons; to increase business, control expense, enhance profitability, gain market share, etc. Technological advances in both hardware and software have significantly changed the scope of what can be amassed and processed. Massive quantities of data, measured in petabytes and beyond, can be centrally stored and retrieved effortlessly and quickly. Seemingly disparate sources of data can be cross-referenced to glean new meanings when one set of data is viewed within the context of another.

In the 1930s and 1940s the volumes of data available were miniscule by comparison and the "processing" of that data was entirely manual. Had even a small portion of today's capabilities existed, the world as we now know it would probably be quite different.

Should organizations' ability to collect and process data on exponentially increasing scales be limited in any way? Does the fact that information can be architected for a particular purpose mean it should be, even if by so doing individual privacy rights are potentially violated? If data meant for one use is diverted to another process which is socially redeeming and would result in a greater good or could result in a financial gain, does that mitigate the ethical dilemma, no matter how innocent and pure the motivation?