The Constitution of the United States very carefully delineated what constitutes treason, as all the founding fathers were acting as traitors to Great Britain. Treason "against the United States shall consist only in levying war against them, or in adhering to their Enemies, giving them Aid and Comfort. " I, and many others, believe that Donald Trump's press conference with Vladimir Putin on July 16, gave "aid and comfort" to Russia, especially when the president declared that he believed the assurances of the Russian leader over his own intelligence services.
The Constitution is even more careful about a conviction for treason -- it requires "the Testimony of two Witnesses to the same overt Act, or on Confession in open Court." Neither seems likely to happen, although I found Rachel Maddow's reportage last night on the Russian spy, Marina Butina, intriguing. Maddow asserted that the prosecution's papers included the charge that Butina had successfully influenced Trump not to appoint Mitt Romney as Secretary of State, but to choose a figure more acceptable to Putin. Rex Tillerson, the ultimate choice, had been given a medal by Putin. (It was Tillerson who later called Trump "a moron.")
Even in the darkest days of our republic, charges like this are virtually unheard of -- the only exception is just before the Civil War, when some previous presidents were accused of siding with the Confederacy. We are indeed living in interesting times, which a Chinese proverb considers a curse. It will indeed be interesting to see what happens.