There is something very broken in a party that could nominate Donald Trump. While victory is unlikely, he does have the second best chance of anyone to end up president January 2017, and even assuming he does lose there's a good chance that 40+% of all votes cast will be for him, and that represents a large fraction of our population that is ok with a racist, sexist, man-child as president of the United States.
There is absolutely no way that any thinking, caring, or frankly, just breathing person could believe that he is qualified. So any vote for him is demonstrating a desire to burn the United States Constitution, and perhaps the world beyond. I suspect that he is too stupid, incompetent and lazy to actually be as destructive as his rhetoric would imply, but just his becoming president would wreak havoc.
A lot of people don't like Hillary Clinton. I'm not a huge fan (though for very different reasons than you hear about from the mainstream media...seriously, the emails? the foundation? press conferences?). Yea, there's some poor judgement, but to compare her problems to Trump it's like the difference between accidentally stepping on someone's toes because you were staring at your phone to deliberately murdering someone along with their entire family, friends, neighbors, bombing the city they lived in...
It's not fucking close. This isn't some lesser of two evils Mussolini vs. Hitler. It's Anne Hataway (you may not like her but she's going to be good at the job) vs. fucking Donald Trump...I tried to think of a comparison, but to be fair most horrible people are still way more competent than he is he's like a clown pretending to be Stalin or something... Oh, maybe Kim Jong-un, but I'm not sure he's got enough power to count.