This guy actually watched Trump's entire speech in Alabama (read the description!), and observes:
1. Approximately half of the talk was devoted to narcissistic bluster. Whatever issue he addressed in passing, Trump would interrupt himself to talk about himself. (Surely the pompadour hairstyle is the appropriate one for so pompous a figure.) His solipsism would not be problematic were he just your drunken uncle at Thanksgiving, who entertains and amuses you. But Trump is making messianic claims that resonate among at least a quarter of registered Republicans, who comprise maybe one-third of the electorate. Among registered independents, another one-third, he gets even more support, according to polls. They love his hot air and are possibly gravitating towards a real personality cult. Those are usually bad.
2. The lack of content, too, is troubling. Not that I personally like the content of any of the rival candidates’ speeches...[b]ut at least the others are supplying details about their programs and to some extent appealing to reason. Trump appeals purely to emotion, to faith (in him), to barely disguised racism and mindless nationalism. This too is bad, reminiscent of fascism.
3. Exhibiting a complete lack of knowledge of the Middle East, Trump has declared that as president he would “put boots on the ground” again in Iraq (and maybe Syria), encircle and seize the oil fields funding ISIL, and “take the oil for the United States.” In the Republican presidential candidates’ debate August 6 Trump boasted that he was “the most militaristic person there is.” While some note that at some point he came to oppose the Iraq War (as “stupid”) he is the opposite of an antiwar candidate. (Not that there are any I’m aware of with any prospect of getting elected.) His bravado about nobody messing with the U.S. under his leadership, and making the U.S. military juggernaut even “stronger” is scary.
All apt observations, but the real question is how much of the electorate (outside Alabama and Texas, say) will go for this? African-Americans and Hispanics will vote against him by landslide proportions; so will women. We saw in 2012 that Republicans can't win nationally when the only vote they can count on is white men. So I still think the longer Trump lasts, the more destruction to the Republican brand he will produce.