Senator Manchin wants other countries or regions such as the European Union to go first with the global minimum tax of 15%. Holdouts Poland and Hungary have not agreed to the 15% tax in the EU. After that the US could follow. Mr. Manchin is a Democrat whose vote is needed for Congress to pass the legislation. Currently the tax is set at 10.5% after legislation passed by president Trump.
Much of the funding for HEIRS - for Health, Education, Infrastructure, Retirees and Society- has to come from better collection of taxes, so that everyone pays their fair portion of taxes which tech companies are not doing in the last decade.