The reality of climate change means that low-lying coastal cities are becoming what we call “stranded assets.” This is defined by financial analysts as “something that has become obsolete or nonperforming well ahead of its useful life, and must be recorded on a company’s balance sheet as a loss of profit.” How can an entire metropolis be considered “nonperforming?” Consider the example of Miami. The physical installations, infrastructures and architecture upon which Miami are founded were built on what we now can see as a flawed assumption: that the sea’s surface would stay as it had for the entirety of human experience. That’s not happening, and the city is already suffering from flooding even when it’s not raining. When the irrational exuberance about the value of coastal real estate pops and thousands of buyers collectively mark down those assets, it will make the housing bubble of ten years ago look like a small blip. The consequences will reverberate through the economy, through society and through the political landscape.