One thing I like about Americans is their desire to dream big. This is easily demonstrated in this New York Times piece about expanding Manhattan.
It’s a smart idea. Is it doable? I don’t know. I do know that the cost of shoring up Manhattan to deal with global warming is going to be a big one. Why not use real estate and additional taxes to do that? Read the article and see what you think.
1980s me would have laughed at the idea of expanding Manhattan, since so much of the existing island was unlivable. Amazing how much has changed.