Leaving out the political and ideological angle, would Trump risk angering Boeing, Raytheon and hordes of other contractors (and their employees) by cancelling an approved deal?
Interestingly, it was the Qatari Defence Ministry that said this deal would create 60,000 jobs in 42 U.S. states. Imagine if the deal was cancelled: His rivals would say that Trump was acting tough with a very fringe player, while larger and more influential states (like the UAE and KSA) got away.
So growing opium and selling heroine ought to be legalized in the U.S. because of the huge number of jobs they will create?
No. Not EVERY decision can be supported ONLY because how many jobs MIGHT be involved. Some situations have priorities beyond jobs.