The leader of the richest and most powerful nation on earth has just cut funding for the UN agency dedicated to the fight against global disease. What does this say about the ability of the international community to join forces to combat the threat of Covid-19? Stephen Sackur speaks to the former British Prime Minister Gordon Brown who is leading an effort to get G20 leaders to commit to a massive joint response to the pandemic. Is there any hope of real global cooperation in the current geopolitical climate?