Alinsky - blame your opponent for what you are responsible for.
ISIS grew to power under the watch of Obama/Clinton - long before Trump came onto the scene as a candidate. They are the ones solely responsible for ISIS recruitment. Trump has them dead to rights on this one and if she tries this in the debate, he’ll nail her on it.
The immigrant problem stemmed from a failure to contain and defeat ISIS, which emerged and grew under Obama and Hillary’s watch. They are responsible for this mess.