PARIS, France—A man in a crowd of onlookers slapped French President Emmanuel Macron in the face when he was on a walkabout in southern France on Tuesday, video showed. Macron’s security entourage pulled the man to the ground and moved Macron away. Two people were arrested, BFM TV and RMC radio reported. Prime Minister Jean Castex said the attack was an affront to democracy. Macron was on a visit to the Drome region in southeastern France, where he met restaurateurs and students to talk about returning to a normal life after the COVID-19 epidemic. In a video circulating on social media, Macron, dressed in shirt sleeves, could be seen walking towards a crowd of well-wishers standing behind a metal barrier. He reached out his hand to greet one man, in a green T-shirt, with glasses and a face mask. The man could be heard shouting out “Down with Macronia” (“A …