http://en.wikipedia.org/wiki/Irgun
http://en.wikipedia.org/wiki/Lehi_%28group%29

I looked through these links, and I was already familiar with the Irgun and the Stern gang. While their violence was indeed deplorable, it also occurred as a consequence of Arab violence against Jews in the region.

I couldn't find the Barak quote. Maybe I'll run into it at some future time.

But, again, for me, it's not an issue of moral equivalency due to senseless violence on both parties. It's an issue of what do these people want. The stated purpose of the Hamas leadership is to destroy Israel, while Israel's stated purpose is only to have security for its people. For me, that tips the scales in favor of Israel.