"just as guilty" is a false equivalence. The Left has much to answer for certainly; but the claim that there is somehow comparable bigotry in both sides of the political spectrum is not remotely credible.
Malcolm X and the Nation of Islam met with the KKK in 1961 despite mutual hostility that would never be ameliorated [2]. In 2016, your entire career can be ruined simply for holding the "wrong" opinion. Boy how things have changed.
[1] https://www.amazon.com/48-Laws-Power-Robert-Greene/dp/014028...
[2] http://www.vice.com/read/when-malcolm-x-met-the-nazis-000062...
Has nothing to do with the Left Wing.
"hold(s) different opinions from oneself" isn't the only characteristic of Nazis, they have other attributes which do justify not tolerating them.
But yes, if it wasn't those attributes, you could still "tolerate" them, in the sense of allowing their opinions to be heard. You don't have to agree. You can even explicitly argue with them.
Tolerant of | Tolerance | Yes
Intolerant of | Tolerance | No
Tolerant of | Intolerance | No
Intolerant of | Intolerance | Yes
It's a little nicer as a 2x2 table, but whatever.You cannot correctly come to a decision about the latter, without listening, which requires the former.
Are you familiar with "point-free style"? (https://en.wikipedia.org/wiki/Tacit_programming) The above crude table should be read as given: point-free. I don't care about the subject of [in]tolerance even slightly (opinions, smells, beliefs, quasi-scientific theories, what-have-you).
If you are tolerant I will tolerate you, if you are intolerant go screw.
"It's so simple!"
Of course the subject is relevant. "if you are intolerant go screw" - does that mean you are intolerant?