"Crying 'Whataboutism' Doesn't Make The Left's Support For Rioting Go Away"

Again, the actual, grown-up term for "whataboutism" is 'tu quoque.' Tu quoque is a type of ad hominem argument. Commonly, it's a kind of consistence ad hominem. Although people often call it "the ad hominem fallacy, not all ad hominems are fallacious. Many ad hominem arguments are valid (and sound)--especially in cases of testimony. If I expect you to take my word (i.e. testimony) for something, then certain ad hominems will be valid--e.g. if you accuse me of being a liar, or of being ignorant of the matter about which I speak. One is apparently supposed to be guilty of "whataboutism" if one deploys a consistency tu quoque against someone. 

   My general view about such arguments is that they often grind to a stalemate on account of being insufficiently clear. If the right's argument were this:

    The left defended/praised the BLM/Antifa riots 

    Therefore:

    The Capitol riot was defensible/praiseworthy

...Well, that seems to be an invalid argument. (Non-deductively invalid, I mean. Obviously deductive validity isn't at issue here.) 

   OTOH, if this is the argument, it may be valid:

    The left strongly defended/praised the BLM/Antifa riots

    The left strongly condemned the Capitol riot

    The two are too similar to sustain such disparate judgments

    Therefore:

    The left's judgments about the riots are inconsistent

 Well...that's a pretty strong/valid (again: non-deductively valid) argument. Is it sound? Well, the first two premises are true. Everything really turns on the third premise. Which I think is true--or true enough to do the trick. But: reasonable people disagree about it.

   At any rate: usually people aren't quite sure what they're arguing in cases like this. They often don't have determinate intentions/beliefs. 

   My own view is that the Capitol riot was disgusting, crazy, and ostentatiously f*cked-up. But there seem to have been a wide range of people and, hence, aims and intentions. Some were just stupid and pliable. Some had genuinely nefarious aims. Some were leftist agents provocateurs. Some seem to have been rightist APs. Some were let in by cops. Some broke in. Some forced their way in. What happen ought to be strongly condemned...but, as usual, the left seems to be exaggerating the wrongness of the thing and using it for political ends. It's not that the right doesn't do such things--it's just that the right is so powerless and voiceless that it basically spends all its time playing defense. 

   The BLM/Antifa riots were far more substantively destructive. And the left has perpetrated and/or defended just about all the components of the Capitol riot: they've attacked and occupied government buildings, used violence to achieve political ends, mounted organized opposition to governmental authority, undertaken acts such that deaths were foreseeable consequences of those acts, destroyed property, desecrated symbols of the country...and done it all for false reasons. 

   Now, of course, one act can be worse in virtue of combining many such elements into one. 

   And arguing that the left is being inconsistent does not necessarily excuse the Capitol riot. But the following is a reasonable position:

The Capitol riot was very bad, but we're not yet sure exactly what happened, nor sure how bad it really was. The left seems to be exaggerating its badness--likely for political ends. The left, now being radical, has a penchant for inconsistency. It is not reasonable to "valorize" the BLM/Antifa riots and hyperbolically condemn the Capitol riot. The fact that the left is so often inconsistent about such things--and permitted to be inconsistent--is the source of much contemporary political irrationality. Some degree of consistency is required.

   None of this rolls Trump into the picture...but I've got stuff to do, yo.

[Oh, and: none of this takes into account the argument that the left, basically, created conditions under which riots came to be considered not merely possible and not merely permissible, but downright laudable...]