I'd been to the Brooklyn Heights promenade several times at night recently, and looked down curiously at this area, but not until I was finally there during the day did I realize this is supposed to be a memorial garden for 9/11. I'm sure the intentions were good, but have you ever seen a more miserable garden? It's right under a highway. It's surrounded by industrial waterfront, with an ugly perimeter fence. The only indication of its purpose, other than the shape of the towers, is a rather tacky real estate-style billboard. And I'm no botanist, but it appears to my untrained eye to be largely filled with weeds (though I suppose it's to the gardener's credit they got different weeds to grow inside the tower shapes). You could say that any garden, or any memorial garden, is better than nothing, or better than the gravel and debris that might otherwise be here. But I think this constitutes a pretty strong counterargument.

PS here's a photo of what it looked like in November 2002. Better, to be sure, but still not what I would readily call a garden, except perhaps in the Zen sense.