Either an idiot or a charlatan. Most likely later. He is a commie in all but name. He wants to kill capitalism - no middle way, and bring everything under Govt control. He becoming the DNC primary, as the chances are, is going to be clincher for Trump 2020. Yes, some young Republican vote will go Bernie way, but a larger % tax paying independent vote will swing to Trump. In fact, many DNC voter would seat it out rather than vote a commie. His cheer leaders are nuts like AOC, jihadis like Ilhan Omar. It is more likely something will happen and Warren would get nomination undercutting Bernie. The DNC establishment is caught between rock & hard place. They have promoted socialist ideas for such a long time that the probable nominees are now smelling like anti- capitalism verging on communism. A flavour that a good part of core DNC voters don't like. That is why they wanted to launch Michael Bloomberg in Las Vegas which was torpedoed by combined attack by other candidates led by Warren.
Any sane and logical American understands the policies Warren and Bernie proposes will hit the free market economy of USA and essentially damage its standing as market leader forever. When there's a chance a compulsive lier like Warren might not go through her poll promises, Bernie - who actually is an outsider to DNC and rather climbed on to the DNC bandwagon simply because an independent never has a chance in the essentially bipartisan electoral system of USA - is most likely would go on carrying out his promises or threats - as you call it. In fact, the establishment i.e. the deep state as you may call it, is so panicked that they have begun compromising Bernie campaign already. The Deep State hates Trump, as he is a loose cannon that is not controlled by them. But Bernie is more of an existential threat to them, as they would lose control over the wider spectrum globally if US economy takes a hit due to Bernie's crazy commie ideas.
Anyhow, even the MSM cheerleaders of DNC that is every media but Fox, is calling Las Vegas to be a win of Trump. So I believe we actually will see a Trump 2020. Nevertheless, when neither DNC nor GOP can be counted as a constant friend or foe of India, the present DNC line up essentially is more anti than pro-India. So, I would rather deal with erratic Trump who has been consistent with his 'friendship' with Modi rather than any of the loonies of current DNC line up.