Three quick points.
1. If Bernie had more delegates and/or more popular vote I am pretty sure the superdelegates would back him; he does not have either, so they won't. Even if you disagree about what they would do if Bernie was ahead with the people, the fact remains that he isn't and won't be by the time of the convention, so I wouldn't say they made the result undemocratic in this case (or historically).
2. Having as President a man who is trying as hard as possible to be a dictator is bad even if he is doomed to fail; I reject your argument on this ground.
3. Saying what's on your mind is in and of itself a good thing but when what's on your mind is horrible that doesn't make a good potential President.
"I would bring back waterboarding, and I’d bring back a hell of a lot worse than waterboarding." - Donald Trump
I agree somewhat with your first counterpoint. Hillary did win the popular vote in hindsight. However unless I'm mistaken the superdelegates had opted for Hillary pretty much from the start.
Your second point is unsubstantiated. You have made an absolute statement without providing evidence. From the empirical evidence I can see that Trump is partaking in a democratic political process and has defeated the establishment candidates in spite of the republican party's resistance. Unlike the democrats however, they did not have the added buffer of superdelegates. I get that you are opposed to Trump but you cannot simply dismiss the democratic expression of voters that voted for him just because you do not like the guy. As of yet nothing he has done can be said to support the notion that he is attempting to become a dictator.
Your third point is purely subjective. Trump has indeed made a number of silly statements but has pretty much reigned most of that in since it became apparent that he was the frontrunner on the Republican side. Once you get beyond the rhetoric though I think that a lot of what he talks about does have merit.
A quick review - "Let's make America great again" - It seems evident that America has allowed its industry to become outsourced and is teetering economically due to its crushing debt. Socially it has been a long time since the country has been so polarised. Therefore I agree with the premise of the statement.
4. "I will build a great wall" - I don't think anyone took this quote seriously. A logical argument can be made that he is simply talking about strengthening border controls which appear unable to cope with the massive illegal flow of migrants from Mexico.
"When Mexico sends its people, they're not sending they're not sending the best" - While this may come across as offensive he is essentially right in the sense that those that cross the border illegally aren't exactly the best that Mexico has to offer as they were unable to immigrate legally. That can be the result of a number of reasons including insufficient qualifications or indeed a criminal record.
I will leave it at that for now but we can see that although what Trump says is often colourful and very much politically incorrect, what he says is often backed up by the facts on the ground.
1. Right, the superdelegates have been more or less backing Hillary from the start, and it's probable that politically speaking the fact that they were perceived to be in Hillary's camp made it tougher for Bernie Sanders to gain momentum. But at the end of the day they are going to vote for the one with the most popular support and I am confident that would have been the case even if Bernie was that one. I don't think we have a major disagreement on this.
2. I am not completely sure we are on the same page here. My intention was to make a counterargument to a specific argument that it seemed to me that you were making.
You said, "The insinuation that Trump can somehow kick out millions of people if he becomes president is ludicrous hyperbole as the US system contains within it substantial checks and balances which in turn makes it virtually impossible to act like a dictator."
That sounded to me like you were saying, Even if he wanted to try to do dictator-like things, it wouldn't matter because the system of checks and balances would stop him. And so I responded, If that was the case, it wouldn't be OK that he is the kind of President who would try to do that just because he is doomed to fail. ("Having as President a man who is trying as hard as possible to be a dictator is bad even if he is doomed to fail; I reject your argument on this ground.") So this isn't actually intended to get into whether he would actually try to be a dictator; rather I am rejecting the argument that it doesn't matter whether he would try to do be a dictator because the system would stop him.
2b. I don't know why you would claim that I was saying anything about Trump seizing the Republican nomination undemocratically. That has nothing to do with what actions he may or may not take once in office, or after getting the nomination (before the election) for that matter. Where did you even get this idea?
3. I don't accept the excuse, "Oh when he was all in favor of torture that was just crazy talk and we shouldn't worry about it." He said, "I would bring back waterboarding, and I’d bring back a hell of a lot worse than waterboarding." In relation to the Brussels attack, when Wolf Blitzer asked how long Trump would like to try non-torture options for interrogation before turning to torture considering that Belgian authorities said the one they had in custody was talking, Trump's response was, "he may be talking, but he'll talk a lot faster with the torture." I don't normally consider myself a one-issue candidate, but fuck that. And if he didn't really mean it? Then fuck that, too. There's a lot of bullshit in politics, but there are actually a couple of lines left to not cross.
4. He has made repeated specific comments about building the wall, that it will be many feet high, that it will cost billions of dollars, etc. He may go back and forth on the specifics, and I don't think anyone really believes that the wall literally "just got ten feet higher" when he retorts to Mexico's denials that they will pay for it, but if you're claiming Trump never intended for the wall to be taken as a literal physical proposed wall then I think you're going to have a hard time explaining what he said back in February:
"And of the 2,000 [miles], we don't need 2,000, we need 1,000 because we have natural barriers, et cetera, et cetera, and I'm taking it price per square foot and a price per square, you know, per mile, and it's a very simple calculation. I'm talking about precasts going up probably 35 to 40 feet up in the air. That's high; that's a real wall. It will actually look good. It'll look, you know, as good as a wall is going to look."
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That doesn't sound very metaphorical to me. Maybe he doesn't stand by his plan anymore, but he did propose to build a literal physical wall and he stood by the basic idea of that plan for a long time. I don't know what the most recent proof is, but I don't know of any proof that he now considers it a metaphor either.