There are a lot of interesting two-steps in this article. For instance, Roberts makes an argument with direct and obvious implications about electability - but he's careful to insist that this "is not an argument against supporting Sanders." Instead, he's merely suggesting that Sanders supporters should "get a thicker skin," an innocuous point sure to divert "the social media bile surely headed" his way.
In another two-step, he concedes that Republican attacks on Clinton have "already driven her unfavorables pretty high" - but then he insists that she "has survived them" and proven "resiliient in the face of attack". Which is it? Acknowleding the impact of attacks on Clinton over the years means acknowledging that she has been damaged to the point of endangered electability. No other candidate for president in modern American history has seen leads as insurmountable as Clinton's collapse so catastrophically, and repeatedly, as soon as she is challenged.
The most egregious two-step, however, has to be his attack on Sanders himself:
Meanwhile, the left insurgent candidate, Bernie Sanders, has also had a mostly free ride...If you say something like this on social media, you'll be beset by furious Sanders supporters. (If there's one thing it's easy to do on social media, it's get yourself beset by furious Sanders supporters.) But it remains true that Sanders has faced very few serious attacks.Roberts then lists the serious attacks Sanders has faced: critiques on gun control, health care reform, his identification as a socialist, and his theory of political change.
What deserves some direct and personal explanation here from Roberts are his glaring omissions of what have clearly been the most serious attacks on Sanders: the constant, hyperbolic accusations of sexism and racism that have beset his campaign since day one. These are obviously the attacks that have most inflamed Sanders supporters, and that have provoked the most passionate and adamant responses; they are the attacks that are always at stake whenever anyone starts hand-wringing about "Berniebros", rude teens, and belligerent Twitter eggs. They are at the very least - one should hope that we can all agree - attacks that are serious.
So we get the third and most inexplicable two-step: Roberts accuses Sanders supporters of reacting to criticism "in tones of barely contained outraged, as though it is simply disgusting what they have to put up with" - but then, he completely omits the attacks they are specifically reacting to, and pretends this is all about dry innocuous policy disputes about things like single payer.
Ultimately, the problem Roberts faces is that that campaign Clinton has waged against Sanders has not been all that different from what you would expect from a Republican. She has even hit Sanders on all three points that Roberts sees as "vulnerabilities" against the GOP - his age, his socialism, and his tax policy - but her campaign has gone much further than that with extraordinarily negative and cynical attacks accusing Sanders of sexism and racism. This is what makes the argument that Sanders has "had it easy" so self-defeating: it points us to the fact that Sanders is easily withstanding the very worst that Clinton, the self-styled partisan warrior and political knife-fighter, has been able to dish out.