<p>Decarbonizing global shipping is crucial to achieving international climate goals. However, efforts in this field may be inhibited by geopolitical risks that profoundly affect global shipping. Here, we use natural language processing on an over 500-million-word corpus to quantify the shipping decarbonization attitudes of 52 countries. Using a causal inference approach, we provide evidence that geopolitical risks exert a substantial and statistically significant negative impact on national decarbonization willingness. This dampening effect threatens to delay the International Maritime Organization’s timeline for zero-carbon shipping. Causal evidence also reveals that countries facing geopolitical tend to prioritize economic efficiency over environmental concerns, particularly those with high levels of maritime trade, economic development, and carbon intensity. We further validated these shifts by analyzing carbon dioxide emissions of global vessel navigation. This study highlights the urgent need to bridge geopolitical divides to achieve the ambitious target of zero-carbon emissions in global shipping by mid-century.</p>