DPA Reform Act of 2023 This bill modifies the Defense Production Act of 1950 by requiring that there must be a declaration of war to exercise authority under the act. The act generally gives the President certain authorities to influence domestic industry in the interest of national defense. The bill provides that there must be a declaration of war for the President to exercise authority under the act related to (1) priorities and allocations for materials and services; (2) the expansion of productive capacity and supply; and (3) general provisions, such as those related to appointment policies.