In most Western countries with Christian orientation, the question itself is pretty obvious. ‘Belief in God’ for a typical American would usually be accompanied by some common Christian behaviors, and since many of these are optional, it could be translated into simple everyday habits. Nothing special that can be recognized by an outsider, unless they specifically ask.
Not so for an observant Jew. The amount of strict rules enforced by Orthodox Judaism is enormous, many of which are directly related to how one is dressed, how they talk, what they eat, you name it. Hence, asking a Jewish person ‘are you religious’ – seems unnecessary. If they are, you quickly see it without asking.
So far, the minority of Israeli citizens of Jewish origins would answer ‘yes’ and be classified that way. Yet, a recent survey revealed 80% of Israeli Jews ‘believe in God’… What is the meaning of this? How can one define him or herself as ‘secular’ and believe in God at the same time?
I suppose the explanation has to do with both the way we are brought up and the way our mind has evolved, but whatever the reasons are, the road from ‘secular but believe in God’ to ‘religious’ is pretty clear. It is that road that poses the real danger to the future of modern Israel.