"Where does Hamas get all that money

and are their leaders really billionaires?"

It's a question I heard yesterday and I have heard similar questions before. No doubt I will hear similar questions again.

I can take a reasonably well educated guess at the answers to that. Hamas controls the Gaza strip and will continue to do so even if they claim "free and fair" elections have been held. They control what goes into Gaza. I am not talking about the humanitarian aid which goes into Gaza but the other goods which go in, mostly through the network of underground tunnels starting in the Sinai. 

Gazan residents pay highly inflated prices for these goods. They are also heavily taxed in other ways. The taxes are largely used to support Hamas, not the Gazan residents.  

The other source of income for Hamas is donations, particularly from countries like Iran and Qatar. Hamas uses some of this income to invest in real estate projects in places like Saudi Arabia and Syria as well Iran and Qatar. It is estimated they have an income of at least one billion American dollars a year because of all this. 

The leaders of Hamas, men like Khaled Meshaal and Ismael Haniyeh, are said to be billionaires. I have no idea whether that is true but there is evidence they live very comfortable lives far away from Gaza. They appear to be able to do this when it seems the unemployment rate in Gaza is above 30% and more than 60% of the population lives below the poverty line. Hamas is thought to be almost as wealthy as the Islamic State terrorist group - and both groups are far wealthier than something like the Taliban.

Of course keeping people in poverty and blaming the existence of Israel for their plight is a good way of stirring up resentment and trouble. It ensures there are always people ready to "fight" for what they have been told is theirs. The residents of Gaza actually have a very diverse ancestral heritage. They are by no means any sort of homogenous group of Muslims who were displaced to make way for the state of Israel.  It is much more complex than that.

We get a sort of greatly simplified version from the news sources available to us. The questions being asked are not something I can answer from first hand knowledge but I do know two things. One is that Hamas is not using the money they get for the benefit of the people of Gaza and the other is that the leaders of Hamas do not put their own lives, or those of their families, at risk by living there.