Throughout the years, Saudi decision-making has been characterized by three fundamental principles—discretion, caution and cash. But last month, by deploying troops to Bahrain and lecturing Iran, the al-Sauds acted out of character. They sent an unintended invitation to Iran to intervene around the Persian Gulf, an invitation that Iran cannot refuse and one that might be the seed for the downfall of the al-Sauds and other GCC monarchies.

First some essential background. The al-Sauds, and more generally the Bedouins from Najd, have harbored a visceral hatred for Shia Muslims and especially for Iranians, but said and did nothing during the Shah’s reign given the Shah’s military might and his close relations with the United States. Then the Iranian Revolution brought the Shia-Sunni divide and Iran’s revolutionary zeal to the top of the list of Saudi concerns. The al-Sauds believe the mullahs are untrustworthy and determined to destabilize Saudi rule. The Iran-Iraq War in all its savagery was a gift for the al-Sauds. Iranians and Iraqis killing each other was the best of both worlds; Shia were killing Shia and their two rivals in the Persian Gulf were decimating each other. The conflict fueled even more hatred between Iran and Iraq, further dividing the two for years to come, and leaving them little time and few resources to destabilize Saudi Arabia. Although the Saudis and their GCC allies put up mountains of cash to support Saddam Hussein, it was a worthwhile investment. After the bloody war, the period of standoff between the two Shia powers afforded the al-Sauds continued comfort. It appeared that devastation from the war, along with sanctions and continued policy ineptitude, would keep both countries backward for years to come.

But Saddam’s invasion of Kuwait jolted the al-Sauds. Acting out of character, they threw caution to the wind and invited US forces onto Saudi soil to drive Saddam out of Kuwait and, more importantly, to defend Saudi Arabia from an Iraqi invasion. True to form, the al-Sauds did what they do best—greased the wheels with cash. They, along with Kuwait and Abu Dhabi, paid the US for its war-related expenses, prompting the al-Sauds to believe that the US was a mercenary country with high-profile Americans and their military might for sale. As a result of the war, the rest of the GCC, especially Kuwait—which, ironically, had previously thought itself a power to be reckoned with—began to look up to Saudi leadership.

The US invasion of Iraq in 2003 and the subsequent ascendance of Shia to power there was a new blow to Saudi ambitions. Their worst nightmare was coming true. While they had hated Saddam Hussein, they saw him as useful in keeping Iraqi Shia in check and providing a counterweight to Iran. Hoping for a reversal given the ongoing turmoil in Iraq, the al-Sauds did little to discourage Saudi suicide bombers from going to Baghdad. But matters did not go as the al-Sauds hoped, and the Shia maintained their power in Iraq.

Today, the al-Sauds feel threatened as never before. The Arab Spring has toppled two allies and is threatening others in the region. While Arabs in the street are trading full stomachs for dignity, representative rule, a more equitable share of oil wealth and a say in their political and economic future, the US appears to be abandoning its so-called friends in support of the revolutionaries. The Saudis believe the coming clash in the Persian Gulf is likely to be along the Shia-Sunni divide. But instead of proceeding as they have in the past, the al-Sauds are reacting viscerally against the Shia uprising in Bahrain and have stepped into a hornet’s nest that may well be the opening gambit to a Shia-Sunni clash across the Persian Gulf.

The Shia in Bahrain, though treated as second-class citizens, have fared significantly better than their counterparts in Saudi Arabia and had not even considered overthrowing the al-Khalifas in the past. They have always wanted something along the lines of a constitutional monarchy with the al-Khalifas at the helm, but with more rights and representation. Unfortunately, the al-Khalifas are not free to respond to the legitimate demands of their Shia citizens because they are beholden to the al-Sauds, who finance them and their country. Thousands of Saudi visitors fuel the island’s economy on weekends. Bahrain provides a base for the US Fifth Fleet, something the Saudis can ill afford to do on their own soil. The Shia are the overwhelming majority (70 percent) on the island, but they are being oppressed as never before because the al-Sauds want it so. Why? The Saudis fear that more humane treatment of the Shia in Bahrain would fuel demands and dissention among their own disenfranchised Shia, representing 10-15 percent of their population. So the al-Khalifas must mistreat their Shia to be in step with the mistreatment of Shia in Saudi Arabia! They have brought in Sunni mercenaries to man security forces and have granted them and other Sunnis a quick route to citizenship in order to marginalize the Shia majority in Bahrain. They have “invited” Saudi forces to put down the protestors in Bahrain. They have declared a State of Emergency. They have, reportedly, signed secret contacts with Mossad (WP, April 12, 2011). They have surrounded the largest public hospital in Bahrain. They have arrested numerous doctors, nurses, ambulance drivers and paramedics who treat injured protestors. Checkpoints have been set up where soldiers arrest citizens who show evidence of wounds which could indicate they have participated in protests. They have entered homes in the night and arrested alleged protestors. All this and more they have done at the insistence of their Saudi masters.

Up to now, there is little evidence that Iran has interfered in Bahrain—if it has, its activities have been marginal. The Bahraini Shia have done all they can to distance themselves from the Iranian regime, believing that any association with Iran would bring the wrath of the Saudis on them. Besides, Iran’s economic, social and political achievements are nothing to envy or replicate. All this may now change. How do we expect Iran to react to this blatant reign of terror against Shia instigated by the Saudis with complicity on the part of rulers in Bahrain, the UAE and Kuwait? How will Iran react to being lectured for allegedly interfering in the region? What can we expect Iran to do in response to being overtly threatened by Saudi Arabia and Kuwait? How will their response be further conditioned by Washington’s recent admission of covert operations inside Iran?

Before gauging the Iranian response, we should note the mindset of those who matter in Iran’s intelligence services and in its Revolutionary Guards. They are street smart and tough. Their relations with Persian Gulf Arabs are conditioned by history. They don’t react well to threats, especially from Saudis and Kuwaitis, whom they hold in contempt. They know that today the US could still defend their client dictators, but with difficulty. While the Iranians were in awe of the US as it marched with ease into Baghdad, things are different today. The US is overstretched, fighting two wars in Muslim countries and lending support in yet another. Its finances are near the breaking point, giving it limited ability to confront Iran in the Persian Gulf—much less in Lebanon, Afghanistan and Iraq. Most importantly, only Iran knows how close it is to having a nuclear device. Even the threat of the use of nuclear capability, real or imaginary, would seriously limit GCC and US options.

What is Iran’s reaction likely to be? Tehran will have to decide where and how to undermine Arab rulers in the Persian Gulf, especially Saudi Arabia, along with their protector the United States. Iran has no choice but to stand up for Shia rights if it wants to play a regional role now and in the future. The Saudi misstep affords Iran the perfect invitation to take on such a role more overtly and with much more justification than in the past. What sense of justice could allow Saudi Arabia to enter into Bahrain with force, to kill peaceful Shia protestors and rob them of their basic human rights, but outlaw Iran coming to the defense of oppressed Shia?

Iran’s priority will be to foment dissent and protest in Saudi Arabia’s Eastern Provence, home to Saudi Shia and the location of Saudi Arabia’s major oil facilities, where it can hurt the al-Sauds the most. The next likely target will be Kuwait. Here, it can count on the support of Iraqi Shia. Yes, Kuwait is grateful for Saudi support—but can a little country wedged between Iran, Iraq and Saudi Arabia, and with a 30 percent Shia minority, afford such high-profile rhetoric against Iran? While Saddam’s invasion of Kuwait was predictable years before it happened, I believe that today the reasons that the Kuwaiti regime will be undermined by Iran and Iraq in partnership in the next five or so years are even more compelling. Who will rescue Kuwait the next time around, especially if Iran claims a nuclear capability? Saudi Arabia?