As humankind progresses in giant steps, we also face a series of daunting challenges, crises, and security threats, including environmental degradation, climate change, a sharp decline in biodiversity, nuclear proliferation, epidemics, and terrorism, to name but a few. How to respond to these threats is a test of human reason and wisdom. Climate change is a global security issue to which no country is immune. Scientific understanding of and a proactive response to climate change are required for the sustainable development of humankind.