The finale of the Oscar-winning director’s three-part documentary about the biggest tragedy in 21st-century Black American history is a must-watch. It’s a stirring look at the city’s refusal to lie downIt’s hard to quantify the significance of Hurricane Katrina: the combination of a historic natural disaster and cold systemic indifference towards its impoverished African American victims makes it perhaps the most significant event in 21st-century Black American history. It’s no surprise, then, that more than one major documentary series has been made to mark 20 years since wind, water and a whole lot of racism devastated New Orleans, or that leading cinematic auteurs of two consecutive generations, Spike Lee and Ryan Coogler, have each executive-produced their own.But watching Katrina: Come Hell and High Water, you do wish Lee and Coogler had got on the phone to check they weren’t doubling up too much. The new three-parter – the Lee one that arrives on Netflix to coincide with the w...