one was done through theft and lying, the other was with permission....AND facebook had changed their rules since the O campaign.
The effort was called a "game-changer" in the 2012 election, and the Obama campaign boasted that it was "the most groundbreaking piece of technology developed for the campaign."
The only difference, as far as we can discern, between the two campaigns' use of Facebook, is that in the case of Obama the users themselves agreed to share their data with the Obama campaign, as well as that of their friends.
The users that downloaded the Cambridge app, meanwhile, were only told that the information would be used for academic purposes. Nor was the data to be used for anything other than academic purposes.
It's an important distinction, to be sure, and Facebook is right to be attacked for its inability to control how its user data were being gathered and shopped around. (Facebook tightened its privacy rules on data sharing apps in 2015.)