He doesn't know what he's doing. We're not being hyperbolic, he literally doesn't understand.  To even say he has an Executive Summary understanding of anything would be giving him too much credit.  Even simple stuff like the reason he only eats fast foods is based on a whole chain of misunderstandings.

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You're getting there, Mark!

Mark>>Why don’t any of the people who used to work with him and now hate him

There's a lot of stuff in this post, so apologies in advance for any editing errors.  I tried, but I've only got so much time, you know?

How have you managed to avoid it? That aside, they do.  To the media.  Obviously no one listened, thought they were being hyperbolic, it was just "politics", sour grapes, was lost in the "big news" of the day. Whatever.  It literally cannot be that Trump is an obdurate moron. It's just minor news. Our Dear Leader is the bestest smartest guy ever, surely!  He's playing 5D chess! If he's so dumb, why is he rich?  The crap I see on socials from the randos is gob-smacking.

I recall a joke I heard on Morning Radio here in the Twin Cities way back in the 90's (when I listened to Morning Radio). 

Donald Trump and beautiful woman enter an elevator.  The woman recognizes him and offers him a blow job.

"What's in it for me?" he replies.

Inflicting this kind of harm on the US economy, the Canadian economy, the Mexican economy, the European economy, the Japanese economy, on basically  everyone because, of his stubborn insistence that it's a good idea, without one shred of evidence (practical or theoretical) to back his corner is the kind of thing where Congress should be stepping in to say, hang on, we're going to have to act as a check on your power here, because this clearly isn't about national security, it's about you being a bull-headed autocrat.

It's complicated.  On the one hand, I think he knows exactly what he's doing in the aggregate.  To say otherwise means that he's just a bumbling fool that happened to win two national elections separated by 4 years during a politically divisive time.  He's "lucky" or somehow "stumbled into it". He is none of those things and to consistently say that he is or to otherwise demean it gives voice to those that support him.  He knows, again in aggregate, what weight his words and actions mean.  Full stop.  

Does he know the specifics?  No.  Not at all.  And this gets into the "he doesn't know a thing" category.  No.  He doesn't know the specifics.  Doesn't care.  Can't be bothered.  He has a goalpost and is aiming for it. He's used the former against the latter and leveraged that to get elected not once but twice.  Simple math.  And MAGA eats it up.  

So it's not as simple as "he does or he doesn't".  No. Dude doesn't know the details.  Couldn't care less about the repercussions.  Dude knows optics and the "grand plan" such as it is.  You can be two things at once; smart at one thing, totally obtuse at another.  We've all met people like that.  It's not as binary as one over the other. You can be both.  

When he goes, it's gonna be hard to dig the ticks out.

The situation back then sound very familar. The proposers of the tariffs promised it would create US prosperity, but Canada and many other trading partners responded with retaliatory tariffs. It undermined confidence in US international co-operation and France and Britain developed new trading partners. The tariffs were proposed as a protection for farm workers, but exacerbated the Great Depression and led to a huge loss of farms (roughly a third of farmers lost their land).

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US imports and exports fell by more than 60% between 1929 and 1934. World trade decreased by two thirds in the same period. US unemployment rose from 8% in 1930 to 25% in 1932.

Over decades and decades after WWII, governments around the world worked to remove these barriers to trades and global prosperity ensued. Tariffs are stupid and damaging.