To be exact, many lives lost, but many saved. If the towers were never going to stay standing, why all the extra support? Was it futile after all? Suppose for a minute that the towers hadn't been built with all that reinforcement - that they'd collapsed a few minutes after being struck. The rubble at the side still would weigh a million tons. The site still would have taken as long. But how many more people would have died? It's a figure no one wants to calculate. Thankfully, because a team of engineers and architects made the Trade Center as safe as it could possibly be. To sum up, I first recalled the disastrous episode of the fall of the World Trade Center, then I explained how extraordinary the design is. After that, I summarized the reasons of its catastrophe collapse. That's for today.