Expansion? Let's see. They got the West Bank, Gaza and the Sinai after defeating Egypt, Syria and Jordan in the Six Day War (which kinda makes me question your "demise" statement, when they can defeat three countries at once), and have agreed to give 97% of the West Bank and Gaza land won in the 1967 war to the Palestinians. That agreement keeps getting rebuffed by Hamas in the form of rocket attacks.
I did a Google search for "Israel expansion" and the first page of results were from socialist websites. Funny how that works.
Well, certainly they did not "agree to 97 percent for the Palestinians" - there's a new wikileaks type scandal with that. The released documents show the Israelis rejecting offers of pretty much every important territory by the Palestinians, and then saying "look, it's government policy to just keep building until its ours. You will have to live with it." The release of the documents basically destroyed the Palestinian Authority, because the concessions they were offering made them look so weak.
But apart from your version of the facts or mine, obviously the people who are engaging in these revolutions do not agree with you. Their perceptions matter for this purpose, and they are clearly of the opinion that Israel is an aggressive, expansionist state. They do not recognise any right of people to come to that land from Europe just because they're Jewish.
And yeah, the six day war is a good example of dictatorship fail. Jordan hardly counts - the Hashemites have relied on Israel since its inception. There would be no Jordanian monarchy but for Israel today. The rest of those nations were, to a t, badly managed dictatorships (with the possible exception of Egypt.) And Israel's greatest success was of course starting the war - by hitting first, they took out all air opposition. How do you think Arabs today view that?
Micro, it isn't the Muslim Brotherhood that is a threat. Islamism never was to Israel, which is why Israel has been more than happy to cooperate with Islamists, including Hamas (originally funded by Israel) and Saudi Arabia (maintains close ties with the Mossad). Islamism simply does not have enough mass appeal in the Arab world to motivate big changes.
The real threat is secular Arab reform. That kind of change will get the numbers and motivation to threaten the existence of the state.