That is a tactical consideration and you might very well be right. But the strategic goal is to deny ISIS oil revenue. Trump get the strategy right.
But that's one of my points about Trump - I have not heard him actually flesh out his ideas:
Take their oil...
Build a wall...
Just like at my job, or at church, I cannot take someone seriously who can't hang the details on their sketch.
Everyone's got ideas, some of them are pretty good - but think logistics, man - that's the hard part.