Trump will propose  the creation of an “Arab NATO” during his visit to Saudi Arabia:
When President Trump arrives in Riyadh this week, he will lay out his vision for a new regional security architecture White House officials call an “Arab NATO,” to guide the fight against terrorism and push back against Iran. As a cornerstone of the plan, Trump will also announce one of the largest arms-sales deals in history.
Some version of this idea  has been floating around for a while now, and it makes no more sense now than it did before. The war on Yemen is the prime example of collective military action by Gulf Arab states, and it has been a disaster for Yemen and a demonstration of how militarily inept many of the coalition’s members are. Insofar as an “Arab NATO” serves as nothing more than a vehicle for Saudi-led interference in the affairs of its neighbors, it would be a regional menace and would involve the U.S. directly or indirectly in more of the region’s wars.
Building a formal alliance to “push back against Iran” would guarantee ongoing regional instability for years to come, and it would fuel vicious sectarian hatreds between and within the countries of the region. If the members of this “Arab NATO” conduct the “fight against terrorism” as well as they have to date, jihadists will have little to worry about, since the policies of most would-be members have helped make jihadism flourish in several countries. The U.S. will be expected to support the misadventures of this alliance, and that will implicate our government in whatever other ill-advised interventions they start on their own. Worse, if the “Arab NATO” obliges the U.S. to defend members of this new alliance it will mean more foreign commitments and entanglements for the U.S. Finally, there is no threat comparable to that of the USSR or some other major power to merit a collective defense alliance of this kind, so it isn’t needed.