Green bonds marry environmental finance and risk management. This chapter asks whether they protect investors against tail events. Using daily data on US and Chinese green bond indices from 2016–2024 and copula models that track time-varying extreme co-movements with government bonds, equities, commodities, and foreign exchange, we test hedging capacity before and after COVID-19. Results show green bonds preserve value when conventional assets sag. Their correlations with stocks and commodities remain weakly positive and time-limited; during the 2020–2021 pandemic phase, the link even turned negative in the US, offsetting exchange rate stress. In China, green bonds gained hedging power against bond and forex risk as domestic markets tightened. Across both economies value-at-risk and expected shortfall metrics fall by up to one-third when green bonds are added to balanced portfolios. Policy takeaways follow. Credible green bond taxonomies and disclosure rules can widen the investor base, lower funding costs for climate projects, and enhance systemic resilience. China could anchor market depth by courting offshore institutional holders, while global standard-setting would boost transparency and align safe-haven demand with sustainable development.