It is a mistake to play up the Saudi-Iranian regional rivalry. Comparing Iran to Saudi Arabia is like comparing America to Russia post-Soviet collapse. Both Saudi Arabia and Iran would be foolish to get in a war with each other for sectarian reasons. Saudi Arabia is wishing America takes the lead and bombs Iran. But, America will gain more from a deal with Iran than getting into a war that will be disastrous for both sides and the region as well.
A lot of scholarship has been produced that argues nations go to war for psychological reasons more so than for security reasons. The recent attack on Yemen by Saudi Arabia adds further credence to that argument.
If you read the official statements of Saudi officials you'll notice that they perceive the attack from the Houthis in Yemen as psychological in nature more than anything else. The Houthis were not about to invade Saudi Arabia anytime soon, and they had no reason for doing so in the future because they're not suicidal. They were busy consolidating their gains in Yemen.
In their statements, Saudi officials wrongly overlook the political independence of the Houthi movement and keep referring to Iran's regional ambitions and its rise. They complain that Iran is gaining control over the Arab world, which is not true. They genuinely seem emotionally hurt by Iran's claimed ascendance in the region and its possible acceptance into the international community following a nuclear deal with the United States and the other members of the P5+1.
Saudi Arabia has viewed America's growing relations with Iran only a little more rationally than Israel. It sees the uncertain developments in the region, including in its own backyard, and it is naturally responding from a position of hurt and a loss of pride. It has lost confidence in the U.S., and it perceives Iran as breathing down its neck, wrongly or rightly.
The ugly truth is that the people of Yemen and the nation of Yemen are being sacrificed because the Saudis are psychologically hurt. This is what the war is about, not some Sunni-Shia nonsense.
The fact that the Saudis are justifying their aggression against an Arab country by depicting it as a pawn of Iran when it clearly isn't is all we need to know about how much strategic thought they put into this military campaign. This is not the actions of a confident state. They will be ultimately unsuccessful because they're attacking Yemen from a position of psychological weakness. All the fighter jets and mercenaries in the world can't make up for that.
What is Saudi Arabia fighting for in Yemen? Officially, it is to restore a president to power that it views as legitimate. But it has also stated that it wants to put a stop to Iran's headway into Yemen and fight off the new Iranian empire.
The myth of a new Iranian empire that Saudi Arabia says it is fighting in Yemen is just stupid and baseless propaganda. This propaganda is mostly spread by ignorant right-wing neocons, ignorant right-wing Israelis, and ignorant Gulf rulers like Saudis. These guys are the biggest conspiracy theorists in the world.
They exaggerate Iran's power in Damascus, Baghdad, Beirut, and now Sana'a. They forget that six years ago there were popular protests across Iran in reaction to a controversial election, and that Iranians elected a moderate president in 2013 with a mandate to end sanctions and reintegrate Iran with the global economy. The age of empires is in the past.
Iran has gotten more involved in Iraq and Syria in the last couple of years because ISIS, which Saudi Arabia and the U.S. helped create, was at the gates of Baghdad and Damascus. The Iraqi central government requested Iran's assistance to get rid of ISIS, which it provided immediately. Ditto for Assad.
What was Iran supposed to do? Say no to its new friend Iraq? Say no to its long-time ally Assad? That would've been dishonourable, irresponsible, and stupid. Plus, letting ISIS establish a lawless Caliphate on the ruins of Iraq and Syria that features cannibals and child soldiers would be a big mistake. The people of these countries deserve better than perpetual war and terrorism.
There is no point in trying to convince Saudi Arabia that Iran is not building an empire. They've come to believe it, and they'll stick by their beliefs regardless if the evidence says otherwise. But it is not all their fault for believing this.
The leadership in Iran has been irresponsible by creating the general impression in the region and abroad, whether by purpose or by accident, that it is a regional hegemon with political and military influence in four Arab capitals stretching from the Red Sea to the Mediterranean.
If you ask the rulers of these four Arab capitals who is in charge they'll say they are in charge, not Iran, and they would be telling the truth. They're too proud and independent-minded to let Iran dictate anything to them. And Iran's leadership is not overbearing or bullying in its relations with its allies which is why it has been so successful in winning over people despite all the malicious propaganda that has been spread against them in the region for decades.
Maybe Saudi Arabia should try that approach in Yemen. It may find that people are more responsive to a respectful neighbour than an arrogant invader.