How do positive externalities give rise to arguments for industrial policy?

Positive externalities occur when the benefits of an economic activity spill over to third parties, leading to societal gains that are not captured by the market. This can justify industrial policy, as governments may intervene to encourage industries that generate these externalities, such as renewable energy or education, to ensure their growth and sustainability. By supporting sectors that provide broader societal benefits, policymakers aim to enhance overall welfare and economic productivity. Consequently, targeted industrial policies can help align private incentives with social good, promoting innovation and addressing market failures.