It's Steve Bell's question again

I have already asked about the inexplicable (to me) phenomena of Steve Bell's popularity.

Now about this one:

Could someone explain to me what's funny about that one? Or what's significant in the subject, which I thought to be quite dead after all that transpired with the Scarfe's cartoon?

Of course, I am fully aware of the issue of different tastes and all that, but still - the man is so clearly (to me) mediocre and unfunny. Well, I don't aspire to full understanding of what must be a special branch of the famous British humour, of course...

But please don't tell me Steve Bell is anti- or pro-Semitic, please, I shall have none of that crap.