It is hard to know what goes on in the mind of a man like Donald Trump, but as near as I can tell, his psyche is dominated by compulsions. One of these, perhaps the most powerful, is the need to always be winning, and to get praise for that winning. Whether this comes from lacking love from his father or as a kind of sociopathy, the result is that he constantly craves validation. It is well known that he attacks the media outlets that he consumes, like the Times and CNN, because he NEEDS the TV he watches to praise him. This is also why he has aides prepare him a dossier of positive news every day.
After taking office, the validation did not come. His inauguration was poorly attended, and when evidence of that was broadcasted to the world, Trump set out sentient baggy suit Sean Spicer to scream at the press. The attempt at a Muslim ban foundered. It was quickly apparent that Trump was not going to get his needed adulation by taking this path. Instead of seeking victory through his white nationalist agenda, Trump pivoted to legislation, specifically the repeal of Obamacare. This way he could defeat the man whose popularity seems to torment him. With a Republican Congress, it should have been easy, but yet again he failed.
After being humiliated by that defeat, Trump has retreated into his core principles and his core base, which are both white nationalist in nature. He is back giving his ranting rallies to baying hordes. He has pardoned Joe Arpaio, poster child for nativist violence. He has given aid and comfort to Nazis and Klansmen in his reaction to the terror attack in Charlottesville. Now he has announced an end to DACA, and sent out noted Klan sympathizer Jeff Sessions to announce it.
Knowing that he can't get the adulation he craves, Trump is trying to "win" on the things he cares most about, which are mostly punishing immigrants, Muslims, and people of color. He is a shyster who does not appear to believe in little besides himself, but I would argue that his consistent and unwavering support for white supremacy show that he does indeed have a core set of values. Like a cornered animal, he is set to lash out. With all the scandals looming and his popularity in the toilet, I think the situation is especially dangerous. Failure to stop him is not an option.
There will never be a "pivot" on his part to be more "presidential." The real pivot is obvious for all to see.