Even if he colluded with the Russians it's not treason.
Yes, it is
Like hell it is. Russia is not a declared enemy in a war. And that's how it is defined.
"2) Don’t hold your breath for “collusion.” For all the talk of Russian collusion, there isn’t really a federal crime that matches what the press, critics, and Capitol Hill lawmakers have been calling collusion, a word that refers legally to a narrow segment of antitrust law. And there’s almost zero chance anyone will be charged with treason, a charge that’s available to use only against enemies in a declared war."
How to Interpret Mueller’s Charges Against Paul Manafort
No that isn't how it is defined, this is how it is defined:
Section 3.
Treason against the
United States, shall consist only in levying war against them, or in adhering to their enemies, giving them aid and comfort. No person shall be convicted of
treason unless on the testimony of two witnesses to the same overt act, or on confession in open court.
Which a judge could rule that Russia's cyber attack counts.