That is, the DNC is supposed to be about promoting the chosen candidate to the American people, not actively picking one.
Neither the DNC or any other political party is obligated to hold elections at all. They're perfectly free to nominate a candidate by fiat if they want to. Clearly, as a matter of marketing, they want to be as inclusive as possible and not appear to be picking favorites. But that's purely a PR consideration, not a moral one. As a practical matter, one of the intermediate goals for anyone running for high office is to make sure they have a lot of supporters in the party infrastructure. Only in the general elections do "the American people decide the direction of their government." The parties are free to do as they wish, democratically or not.
Neither the DNC or any other political party is obligated to hold elections at all. They're perfectly free to nominate a candidate by fiat if they want to. Clearly, as a matter of marketing, they want to be as inclusive as possible and not appear to be picking favorites. But that's purely a PR consideration, not a moral one. As a practical matter, one of the intermediate goals for anyone running for high office is to make sure they have a lot of supporters in the party infrastructure. Only in the general elections do "the American people decide the direction of their government." The parties are free to do as they wish, democratically or not.