They will wait for Iran to start it with them.
They withdrew from Lebanon, and got attacked. They evicted people from Gaza because the US asked, and got Hamas. Israel won't even cut off the Hamas-led PA, because they think they might get bad press in Europe if they do. Their credibility is not exactly sky-high at the moment.
In your former examples, Israel was building a case - demonstrating to the world that peace with the Arabs and Palestine was not really possible.
Also, they are now in a configuration where building a wall is possible, and progress is made as we speak.
The reason why they will be pre-emptive here is that Israel is a one-nuke country, and Iran knows it.
They will hit Tel-Aviv, then invade Jerusalem. They'll not bomb Jerusalem because of the Dome of the Rock.
It only takes one nuke to wipe out Israel in the way that the Arab world sees it.