I know it's a hard subject to discuss civilly. I have a modest suggestion on how to improve such discussions.
1) Don't bring up comparisons with Nazi Germany and the actions of the state of Israel (bring up some other horrendous brutal regime if you want to make such comparisons - there are plenty to choose from).
2) Don't call fellow metafilter members anti-Semitic (nor imply they are) because of their critiques of the actions of Israel.
These two phenomenons seem to occur in every discussion of Israel (latest example
Can we all agree that these two things don't help any conversation on this topic?