This bill, titled the Semiconductor Supply Chain Security and Diversification Act of 2025, establishes a policy to enhance the security and diversity of the global semiconductor supply chain. It emphasizes the United States' economic and national security interest in fostering a regionally-based semiconductor ecosystem within the Western Hemisphere, complementing domestic investments made under the CHIPS and Science Act. The legislation directs the Secretary of State, in coordination with other agencies, to support Western Hemisphere governments in diversifying their upstream supply chains , which include critical mineral mining and processing, and their downstream supply chains , encompassing semiconductor testing and packaging facilities. This support involves providing diplomatic assistance for international negotiations, enhancing regulatory environments, and promoting competitive markets. Furthermore, the bill authorizes the United States International Development Finance Corporation to provide financial support for these projects in eligible Western Hemisphere countries. Such support requires a Presidential certification that it advances U.S. national economic or foreign policy interests. This investment must also either yield significant developmental outcomes or be necessary to counter the efforts of strategic competitors to gain leverage or acquire sensitive technologies in allied or partner nations.