First of all, global warming is a problem with potentially cataclysmic outcomes. Everything from food production to urban spaces could be changed drastically. The belt of arable land and that is comfortably habitable may change. It's a crucial
Second, almost all of the private and public efforts to push against global warming are also crucial for every other aspect of sustainability. Reducing carbon use is the only way we will conserve a non-renewable resource, reduce pollutants that harm real people, and protect the planet. We need to have a sustainable system based off of renewable energy. Similarly, restoring old-growth forests and other carbon sinks would be vital to replace the damage we've done to ecosystems.
Third, the efforts to fight global warming aren't just sunk costs. Efforts to push fuel efficiency benefit people. Efforts to switch to sustainable energy creates new jobs and industries. The myopia shown on this front by people is really startling: Crises breed innovation and change.