This month marks 30 years since the genocide in Rwanda led to the deaths of more than 800,000 Tutsis and moderate Hutus in one of the worst massacres of the 20th century. But even though Rwanda has largely recovered, retired Canadian Lieutenant-General Roméo Dallaire says the world hasn't learned the lessons from that time to prevent future wars and mass atrocities. The former commander of the United Nations Assistance Mission for Rwanda tells Chattopadhyay about his own mental health journey over the last three decades and why he's so disappointed in the international community – including Canada – for letting conflicts around the world spiral out of control.