OMG. Some of these comments are based on thin air. 
Fact. When Obama signed the DACA Program as an Executive Order, it was because the stupid Republican lead congress CHOSE not to act upon it, stating that only the congress could enact such a program. They argued about the merits all the while knowing they wanted no action in order to see Obama fail. So Obama decided to use a squeeze through measure that would allow for a Presidential Executive order to enact this program. The response would be that the congress would have to sue the White House for a decision. The few Republican holdouts came from red states that did not care about these children. However, the Republican leaders choose not to sue and instead let the program remain. Trump has been threatened by the same Republican holdouts that they will sue if he doesn't rescind the order, which he has the right to do. Instead of standing up to these bullies, he caved. Leaving it up to congress. Nothing will get done.