Critical Mineral Independence Act of 2023 This bill requires the Office of the Under Secretary of Defense for Acquisition and Sustainment within the Department of Defense (DOD) to submit a strategy to develop supply chains for DOD that are not dependent on mining or processing of critical minerals in or by specified countries (e.g., China) in order to achieve critical mineral supply chain independence from such countries by 2035. The strategy must be submitted in classified form but must include an unclassified summary.