The President and other dignitaries were in New York yesterday to celebrate the opening of the 9/11 Memorial Museum. The museum is a crucial part of the overall World Trade Center project, especially as the years pass and the generation born after 9/11 grows older. It is always somewhat shocking to think of the high school sophomores and juniors on my tours and to realize that they don't remember 9/11. The museum will bring a visceral and personal reminder of the stories of New York in late 2001 and what people experienced on that day and in the months after for generations of young people. But up on the plaza above the museum, where the memorial's sunken pools mark the site of the Twin Towers, something even more important happened with no fanfare at all. A few small lines of fences were removed.