This week New Zealand and France joined forces as world leaders try to put an end to the use of social media for acts of terrorism. Next month Prime Minister Jacinda Ardern and French President Emmanuel Macron will meet with world leaders and tech companies in Paris, to seek a commitment to eradicate violent extremist content online. Political reporter Jo Moir takes a look at what a social media crackdown might mean and whether it can be achieved on the world stage.