You would think all the corruption, grifting, self-dealing would be cause, but I guess not.

Emoluments clause?

Again, the Constitution is not a criminal law. Violating the Constitution is not a crime. Which is a good thing, because Congress and the President are constantly being challenged in court over whether one act or another violates the Constitution. They sometimes lose. They haven't committed a crime if their actions are found to be unconstitutional. That's as true of the Emoluments Clause as any other part of the Constitution.

So if you believe that "high crimes and misdemeanors" refers to....well, crimes, then violating the Constitution wouldn't fall within that phrase.

Now - many actions might violate the Constitution and a criminal law as well. For example, if a federal judge takes a bribe, she will have violated both the Emoluments Clause and a number of criminal statutes. But for issues like whether Congress must give authorization for the type of military action that we are conducting in Venezuela, or whether that falls within the President's Article I power, there's not likely to be an applicable criminal statute and we're just dealing with the Constitution. So it seems to me that would not implicate a "high crime and misdemeanor."