Killing innocent people is NO self-defense. Your death ratio is simply too high that it could be excused over "self-defense" (following this argumentation you could say that all mass murders defended themselves since some of their victims also used force against them). What Israel is doing now is indeed self-defense. Following your advise means to commit a Holocaust. That is a fundamental difference. Since Israel is no evil and barbarian murder connection they will never follw this path.
If your refer to Christ than you should follow and know the most basic and important rules of this religion. To notice this has nothing to do with preaching.
Israel drops leaflets warning innocents about their plans to bomb an area. They are doing more than enough to minimize civilian casualties (a sad reality in any war). They are 100% justified.
They can do as you say and continue to be assaulted for the next thousand years or get it over with.