50 USC 842 - Communist Control Act of 1954
This is in full effect.
"The Congress finds and declares that the Communist Party of the United States, although purportedly a political party, is in fact an instrumentality of a conspiracy to overthrow the Government of the United States. It constitutes an authoritarian dictatorship within a republic, demanding for itself the rights and privileges accorded to political parties, but denying to all others the liberties guaranteed by the Constitution. Unlike political parties, which evolve their policies and programs through public means, by the reconciliation of a wide variety of individual views, and submit those policies and programs to the electorate at large for approval or disapproval, the policies and programs of the Communist Party are secretly prescribed for it by the foreign leaders of the world Communist movement. Its members have no part in determining its goals, and are not permitted to voice dissent to party objectives. Unlike members of political parties, members of the Communist Party are recruited for indoctrination with respect to its objectives and methods, and are organized, instructed, and disciplined to carry into action slavishly the assignments given them by their hierarchical chieftains. Unlike political parties, the Communist Party acknowledges no constitutional or statutory limitations upon its conduct or upon that of its members. The Communist Party is relatively small numerically, and gives scant indication of capacity ever to attain its ends by lawful political means. The peril inherent in its operation arises not from its numbers, but from its failure to acknowledge any limitation as to the nature of its activities, and its dedication to the proposition that the present constitutional Government of the United States ultimately must be brought to ruin by any available means, including resort to force and violence. Holding that doctrine, its role as the agency of a hostile foreign power renders its existence a clear present and continuing danger to the security of the United States. It is the means whereby individuals are seduced into the service of the world Communist movement, trained to do its bidding, and directed and controlled in the conspiratorial performance of their revolutionary services. Therefore, the Communist Party should be outlawed."
https://uscode.house.gov/view.xhtml?req=granuleid:USC-prelim-title50-section842&num=0&edition=prelim
https://www.law.cornell.edu/uscode/text/50/841