In your case, I wouldn't worry about the risks of FB as much as about the fact that you seem to keep going back and forth in your thoughts. You just asked us,

In your case, I wouldn't worry about the risks of FB as much as about the fact that you seem to keep going back and forth in your thoughts. You just asked us, a few levels up, to consider the "What-if?" scenario of some future Hitler coming to power, with all your data available on FB. And so people started explaining to you that, yes, in that case, you'd definitely be very naive not to consider the (obvious) risks of having all your data up on FB. To which your answer to that was, basically, "But that's not very likely to happen."