There is no such thing as international law. There are treaty obligations which must be approved and accepted by the people of the countries involved, or they will be unenforceable.
There is no lawmaking body beyond anyone's borders that people have elected, which people are obliged to obey. We occasionally point to this or that UN Declaration in building the case for something we are about to do, but we do that for political and propaganda reasons, not because the Declarations have any legal power.
Israelis have the right to defend themselves. They don't have it if some foreign power gives it to them, they have it because they have it. They will have to assert it themselves, however, with all the risks and dangers and bloodshed that comes along with asserting it. Thats what it means to be "independent" and "sovereign". You are independent and sovereign if you are willing to do your own fighting and dying and do it by your own decision.
An excellent post, which I can only second. No more need be said.
Quite right. There is no such thing as international law. That hasn't stopped a few reformers from pushing ahead as if there were.