What are the implications of a rift between a Pope and a world leader?

Donald Trump’s onslaught against the Pope is almost overshadowing his first visit to Africa.  

The US president accused Leo of being soft on crime, untroubled by the prospect of a nuclear Iran, and in league with the radical left. Trump’s angry about the pope’s repeated criticism of the US and Israeli war on Iran. 

But Leo says he’s not afraid of Trump. 

Has there ever been such a deep rift between a pontiff and a major world leader and what are the implications? 

GUEST:

• Vatican historian and commentator Professor MASSIMO FAGGIOLI is with Trinity College, Dublin.