Building off of the potential increases in power of Iran following the recent nuclear deal with the P5+1 comes the issue of how Saudi Arabia will react to this change in the balance of power.
With an increasing Iranian power the region will shift from a Saudi centered unipolar power dynamic to a bipolar system in which the two powers will offset each other. This has the potential to create a regional mini cold war.
One of the many issues associated with a cold war is the increasing likelihood of proxy wars. This currently appears to be the case in Yemen following the Saudi response.
An interesting op ed by David Roberts in a recent BBC news article titled “How far is Saudi-Iranian Rivalry Fueling Yemen War?” addresses this very issue.
What Roberts argues is that this is not a sectarian issue as many in the media have played it off to be. The Saudi’s historically have had no issue with the Shiite Yemen. This issue only came about in recent years. Further the evidence of cooperation between the Houthi Rebels and Iran is much lower than previously reported. There are many discrepancies in the previous reporting of this conflict with the association between Iran and the Yemeni conflict.
In reality this is much more of a response by Saudi because they are feeling encircled by the expanding Iranian influence in the region. This is evident across Iraq and Syria most notably. It makes sense that Saudi would panic that there is the potential of Yemen to become loyal to Iran however, this is not currently the case. Ultimately, this appears to be more of a preventative scramble to ward off a future possibility of an encircled Saudi Arabia by pro Iranian states.