The Democrat party was the original party of slavery. Abraham Lincoln was a Republican. It was the Republicans who fought to free the slaves from the Democrats. The Democrats never forgave the Republicans for that and still hold a grudge. To many Democrats, the black job growth, induced by Trump's policy, is history about to repeat itself. This may free blacks from voting Democrat.
I was watching a series about the Civil War. In discussing southern slavery, not all the Democrats were harsh slave owners. Many Democrats, at the time, like General Stonewall Jackson, were deeply religious, and believed that the blacks could not fend for themselves, being out of their native element. As good Christians, many believed it was their duty to help care for the blacks. To some of the more religious southerns, slavery was a way to look out for them. It provided jobs, to keep busy, as well as room and board. The same would be done for their own children.
After the civil war, the harsher end of the slavery spectrum ended by law. But for many well meaning Democrats, the idea of taking care of the blacks, now out of the context of slavery, perpetuated. For example, during segregation years, the whites would provide the blacks their own restaurants, theaters, water fountains, etc. In harsher times none of this would have been available. To some, it was a way to share culture with blacks.
Trump, by thinking in terms of jobs, is allowing the blacks to have the means, to make their own choices. If you are on welfare, your choices are limited and the choices that remain, come with a price. Trump by giving them jobs, to make their own money, opens options beyond any obligation to big government or the Democrats. This goes against the plan of the Democrats, who are now resurrecting the lynch mob, less it go too far.
A good analogy is the mother who takes care of her child, too much, to where the child never learns to fend for themselves. She does everything for him or her. On the one hand, this makes life easy for the child and makes them feel special. On the other hand, it weakens the child, so they can't develop self sufficiency through their own actions. If someone always cooked for you and served you, you will never learn to feed yourself. The mother thinks she is doing good because her deeds treat the child as a VIP. But deep down, she also knows this is making her child dependent on her, so he/she will have a hard time leaving her.
Trump is like a dad, who wants the child to leave the house, so he can have his wife back. He gets the child a job, so he has his own money, with no strings attached. The child can buy things even the dad may not agree with, since he is his own man. He then encourages him to move out and make a life of his own. Mother is furious at dad, and starts to guilt trip her son and using threats of disowning him/her if they leave. Kanye West left the house and mom is furious at him. How dare you leave me you ungrateful so and so.
Kanye West understands the dilemma of the black inner child, who feels a long historical connection to nurturing mom; kind Democrats. But he also understands that adults need to learn to stand on their own, even if mom; Democrats, says she will disown you, if you leave. The child feels sentimental attachment to mom, but he also feels the call of their own independence. They are stuck in the middle between mom and dad. The difference now, is that dad Trump has made an impact on the child, and many of the black inner children are toying with the idea of independence due to their new found means. Mom is besides herself, because some of the black vote, may be up for play, in the 2018 midterms and beyond.