Oran's Dictionary of the Law (1983) defines treason as: "...[a]...citizen's actions to help a foreign government overthrow, make war against, or seriously injure the [parent nation]." In many nations, it is also often considered treason to attempt or conspire to overthrow the government, even if no foreign country is aided or involved by such an endeavour.
As of today, foreign governments can seriously injure the United States of America by throwing huge amounts of money into the political system. The Constitution gives free speech to AMERICANS. The SCOTUS just gave free speech to communist China. To Iran. To Russia. To any government that can control a multinational corporation.
Five Supreme Court Judges need to stand trial and if found guily, pay the consequences for this greivous act. That's the law of the land, unless they decide to overturn THAT part of the Constituion too.