Hong Kong has long been haunted by the thought of its future. Many of its citizens worry that it will become just another mainland Chinese city. This fear is often voiced as though to ward it off. But it is also spoken of as if it is already a reality. Beijing’s decision to intervene is an aggressive assertion that in the name of “One Country,” it can redefine “Two Systems.” What once worked by seeming to accommodate a spectrum of views now appears more like a fundamental contradiction. The space for different readings of what the coexistence of Hong Kong and mainland China means is contracting.