I have never understood this. And some of reasons have been explained to me by others yet it still makes no sense
Being a Jew is hard. It is seemingly non-stop obligations, with little reward much of the time. This builds resentment and the more unbelieving Jew wants a different way. That is why socialism attracts him, because it is blessings without the obligations.
The problem with that is that, when we make ourselves independent of God then God lets us be independent and unprotected from the world. For the Jew, that can be death.