> In what sense Israel is not a theocracy.

I find this very disingenuous because the person you replied to was talking only about Iran, and stating that Iran is a theocracy in their opinion. They never mentioned anything about Iran, let alone stating that Israel isn't a theocracy.

So asking this question, this way, is quite strange in my opinion.

They said "theocracy with nukes screams nuke them first". If this is true - and it is their stated position - then, since Israel has nukes, either they are not a theocracy or they are begging to be nuked. The commenter has, I think reasonably, concluded that the other commenter doesn't think Israel is begging to be nuked, and is therefore addressing the apparent contradiction. It seems entirely genuous.