I was looking at the square mileage of the Tunguska event (830 square miles of forest flattened), rather than the stuff right beforehand about how powerful the explosion was.
And in fairness, the Tunguska event was hundreds of times more powerful than the Hiroshima/Nagasaki nuclear detonations. So it would have made either of them look like a firecracker by comparison. I don't really have a good conceptualization of how powerful nuclear bombs have gotten today, so I had no real basis for comparison.