IIRC aren't you former military?
No, I'm not, but I appreciate that there's a lot of information out there most of us don't have access to.
I'd honestly like to be able to trust that the president has the best interests of the country at heart when he (or she) makes decisions. I can buy, for example, that G.W.B. went into Iraq because he really thought there were WMD's and an invasion was the best way to handle it. There's a lot that could have been handled better after that, but I can believe it's totally possible that choice, based on information he had at the time, made sense. On the other hand, we've had presidents flat out lie to us (Lyndon Johnson/ Gulf of Tonkin?), so I'm always a bit skeptical.
With Trump, I see a lot I can't make sense of, when I try to frame it as "looking out for the good of the country". Like I can't make sense out of alienating our allies while cozying up to despots. I can see talking to North Korea. I can sure see being polite. But some of the praise he heaped on that guy is just not accurate, and I don't see that as appropriate. And when he says he wishes "his people" revered him like the people of North Korea rever "the dear leader", it totally creeps me out. Yeah, maybe that was a joke. I have personal experience with people who say things like that, like they're joking, but they're not. But they're claim it was a joke when you call them on it... It makes me nervous.
For me, personally, above and beyond anything else, my problem with this president is the way he treats people. He might be a smart as he thinks he is, and be might have a better handle on things than it looks like he does. He has demonstrated, to my personal satisfaction, that he has little respect for his fellow human beings. For me, that's a deal breaker. I can't trust someone who finds it so easy to dehumanize other people.