This link was posted by some Left Wing Jews who were sick of marching with Swastikas at peace rallies
I don't agree with much they say, but it highlights a lot about what they are faced with!
One point - should people criticize Israel in it's entirety? I think not - you can criticise the government, but not a wide stereotype of the entire country. e.g. If you don't like the policy of the Abbott government on say climate change or some such, you criticise the government, not the entire nation and it's people.