The middle east has proven to be a sore spot for the Liberals, in attempting to craft a cohesive message. I don't find it particularly alarming that the Liberal Party mirrors the divisive opinions found in the general public. When you have a party that prides itself on being inclusive and embraces the "big tent" approach, this reality presupposes a certain amount of friction. While it may be important to present a united face publicly, it is also unrealistic to expect the goosestep from diverse members.
What is important in moving forward, is that various "interest groups" aren't allowed to bully their position, at the expense of other factions within the party. Jewish Liberals have become increasingly vocal in demanding that the party adopt their perspective. However, the Liberal Party can't be an extension of the Jewish lobby because it effectively alienates other constituencies that are equally important. An inclusive party must draw on various opinions, especially in a circumstance where both sides can claim validity. You can't expect a party to completely adopt a perspective that doesn't have universal appeal. Official party policy must reflect some emotional detachment from an issue that allows for a rational approach.
I would argue that the recent policy purity that has been demanded undermines the premise of free speech and a robust discussion of ideas. In my mind, the Lebanese question is incredibly complicated and doesn't lend itself to simple black and white propositions. It is an open question on how to proceed diplomatically, and it may involve some decisions that aren't endorsed by all subsets of the Liberal Party. Offering to negotiate with Hezbollah doesn't necessarily translate into a lack of support for Israel, but it may simply reflect a simple reading of a permanent reality. Purging people and demanding resignations from those who express this sentiment is a dangerous precedent that shows no recognition of the complexities moving forward, nor does it embrace the idea of a big tent. Everyone who like the party to completely reflect their opinions, however a party that adopts narrow points of view is destined for marginalization. The Liberal Party is "messy" and it really shouldn't be any other way. People shouldn't feel threatened if they express a view that isn't endorsed by everyone.