Make It in America Act This bill addresses domestic content requirements and narrows instances in which waivers may be granted. Specifically, the bill directs the Office of Management and Budget (OMB), acting through the Office for Federal Procurement Policy, to promulgate regulations to standardize and simplify how federal agencies comply with, report on, and enforce the Buy American Act, including guidelines to ensure that a project is not disaggregated for purposes of avoiding the applicability of such requirements. The bill increases American-made content requirements from 50% to 75%. Before granting a waiver in the public interest with respect to a product sourced from a foreign country, a federal agency shall assess whether a significant portion of the cost advantage of the product is the result of the use of dumped steel, iron, or manufactured goods or the use of injuriously subsidized steel, iron, or manufactured goods. The OMB shall establish within it a Made in America Office to maximize and enforce compliance with domestic preference statutes, develop and implement procedures to review waiver requests, ensure that contracting personnel at each federal agency annually complete training on obligations under such statutes, and ensure the development of a domestic supply base to meet federal procurement requirements. The bill directs the Department of Transportation to enter into a technical assistance partnership with the Department of Commerce to ensure the development of a domestic supply base to support intermodal transportation in the United States and to ensure compliance with domestic preference statutes.