The WTC proposals unveiled this week by prominent architects follow some common themes. “In purely architectural terms, the big news was the triumph of the mega-skyscraper. Four of the seven design teams want to put the tallest building in the world at the site. In the end, it’s hard to imagine any scenario in which a truly successful master plan—one that’s at once architecturally inventive and a good use of urban space—is produced within the allotted time.”