The comparable entities are North America, the Middle East and Europe. Then things would change. <-- No, here is why, if you're in Israel you have access to all that it has to offer, same for the US, and same for Europe (EU). The point is 'how much money is there to go around / potential recipient.'
Europe is far less a single economic block than the US or Israel. An American VC is far more likely to invest in a London based startup than one in say Germany, purely because of cultural and language barriers.
