Honestly I think Clinton is a better accelerationist candidate than Trump. When Republicans are in office the democrats co-opt left critiques to their own ends. When Bush was in office, being anti-war was popular because Bush was pro-war. Democrats told everyone that if you just had a democrat president, we wouldn't have problems in Afghanistan or Iraq. The collapse of 07-08 was similarly passed off as republican mismanagement rather than structural problems.
When you have an Obama or Clinton in the White House, the democrats simply start to say wars not bad and the economy is actually good. As time goes on less and less people buy into these fictions and reject the democratic apparatus. As you saw in 2000 when democrats had to owned collapsing manufacturing sector jobs and foreign adventurism, a good amount of left votes went for the non democrat Nader. Still visible in 2016 when democrats partially own the dreary economic outlook and shyt show that is Libya and Syria(Honduras to a lesser extent), where a much larger portion of democrats go for the non Democrat sanders.
Primary differences between the 2000 and 2016 races is that even amidst the economic downturn in 2000, economic memories of 1990s boom still fresh, Iraq hadn't finished up yet, and Sanders' primary run much more palatable to dem voters than Nader's general. Compare these two contests to 1992, and 2008. All three primaries completely dominated by neoliberal candidates(exception to this thesis being Jesse Jackson in 88, but Jackson was a unique candidate in a number of ways; and still lost) with extensive DNC ties and the generals all lacking significant left alternatives.
Evidence seems to show that DNC is best able to bring leftish voters to heel under GOP presidents. Soft Keynesian neoliberals look much better when compared to pure Randians, neo Birchers, and raging white nationalists. Conversely when Obama's and Clintons must stand on their own merits they, logically, alienate vast swathes of the country.
Being that we aren't ever getting the 90s economy back, neoliberals will continue to look worse and worse not by by electing fascists; but by continuing to be themselves.
There is value in maintaining institutions and efforts outside the Democratic Party. I really respect what Bernie has done and is trying to do, but I worry very much about trying to transform the party. I don't think it is really possible and to the extent that it is, that serves to defang radical movements. So I think that's the wrong strategy.
Yes. People act like others haven't already tried to grab the reins of power from the inside before. It's much harder than most make it seem. Integrating yourself and your people can backfire, it has in the past. As you've seen this cycle with many former progressive and even radical outlets and individuals going to bat for Clinton and other company men over lefter alternatives.