The Chicago Children’s Museum wants to build a new home on an unused section of downtown’s popular Grant Park, and a debate over the proposal has been going on citywide ever since the plans were unveiled. Blair Kamin says that the central problem is that those running the museum and the park have yet to take “a hard look at the desultory section of the park the museum covets,” and that they have yet to consider “an expansive vision for remaking this subpar space.”