As an Indian and somebody who studied the non violence moment of Gandhi both in South Africa and India. I can talk about the nature of political movements, I studied in quite a great detail. Even in India, the nature of non violence movement was not completely non violent- Its true that non violence came as a overwhelming force for the British. But the British did deal and perceive violent revolutionary sources as a equally big threat. There is always a big debate in India that Bhagat Singh was an equally big threat to British, as much as Gandhi. There were and continued to be pockets of violence till the Indian independence.

Secondly, violent attacks don't often serve any thing more than 'symbolism'.In this case, there is a century long history, of a persecuted community being settled on already existing nation. Now persecuted community has its reasons, but the existing people see why they are being driven out and find no acceptable reason for that. Add to this, a massive refugee problem, being forced to live densely crowded areas. No adequate supply of food, water, medicine, electricity for 50 years now. Sub human sanitation conditions. Having to endow the humiliation to stop at check points to move around in their own country, watch their land being endlessly consumed by settlers. Coupled with this the occupier has, a endless diplomatic, military and financial support of the biggest super power in human history. The oppressed can do nothing about it, because the military option isn't even an option. Diplomatic doors are closed.

If you feel these sort of people to not get frustrated, something is wrong about your understanding of human emotions.

Its in the human nature to empathize with the oppressed. And in fact this is the biggest problem with the kind of activity Anonymous has done. Israel isn't troubled because websites are going down for a couple of hours, they are troubled that there are people with some power and say in their hands, who empathize with the Palestinians. This is dangerous, and even fatal for the Israelis. Far more dangerous than the rockets themselves.