Its of course easy to attack the Democrats. They cemented neoliberalism, guaranteeing a permanent shift to the right. They've also been happy to embrace unethical foreign policy. By choosing an elitist establishment figure like Clinton, they also created the perfect conditions for forcing Trump on the world. But this is more than that, this is application of political economy. The defence of Democrat uselessness comes from the median voter model. Essentially an adaptation of oligopoly, it suggests that relative consensus will develop. Anything really progressive, at least according to this defence of the bland, will alienate too many voters. This is overly simplistic (and ignores how such centrism has become deeply unpopular). Behavioural concepts inform us of our predictability in our bias. By failing to come out with anything radical, it necessarily encourages a status quo bias favouring Republican inaction. Yep, I do blame the Democrats for having zero political economic sense. Health care has suffered from their lack of progressive purpose.