The popular uprisings in the Arab world have transpired differently in different countries, but most have had at least one thing in common: a "day of rage." These often climactic protests have been organized in Egypt, Syria, Yemen, Bahrain, Tunisia, and Iraq.

Today it was Saudi Arabia's turn, but the Facebook-based pro-democracy organizers were only able to muster small, peaceful marches in the oil-rich eastern provinces, where the country's minority Shiites have been demonstrating for weeks. In the Saudi capital, Riyadh, "disappointed activists counted more policemen and journalists than demonstrators," reports The Guardian's Ian Black. 

On a day when protesters clashed violently with government forces in Yemen and Bahrain, why was Saudi Arabia's "day of rage" such a dud? Here are eight theories:

Heavy Security: In Riyadh, The Washington Post reports, helicopters hovered overhead and police officers set up checkpoints at intersections, mosques, and courthouses where protests were expected.

State Prohibitions: The monarchy prohibited public protests last week after Shiite groups in the east protested against discrimination by the country's Sunni majority. In Riyadh, Black notes, "anonymous text messages" conveyed "dire warnings of huge fines, loss of nationality and expulsion from the country" for anyone who participated in demonstrations.

Religious Prohibitions: Religious leaders, urged on by the government, deemed protests antithetical to Islamic law in the lead-up to the day of rage. Sheikh Abdel Aziz Alasheikh, for example, informed worshippers in Riyadh's central mosque that "Islam strictly prohibits protests in the kingdom because the ruler here rules by God's will." 

Qatif Shooting: Saudi police opened fire on around 200 mostly Shiite protesters in the eastern citty of Qatif on Thursday, wounding at least two protesters in a show of force that Black believes may partially explain "the calm" in Riyadh.

Saudi Political Culture: While countries like Bahrain and Kuwait "have a history of political opposition and protest, and their parliaments, however weak, serve as an outlet for pressure," The Christian Science Monitor asserts, that's not the case in a deeply conservative, authoritarian country like Saudi Arabia, where protests are rare.

Anonymous Organizers: Many Saudis are genuinely interested in political reforms, argues the Global Post, "but even among pro-reform Saudis there was little enthusiasm for the Facebook protest calls because they were made by unknown people who did not have a clear agenda and who may not even be living in the kingdom."

Little Appetite for Regime Change: "Even though Saudi Arabia has serious problems with youth unemployment, official corruption and discrimination against women and religious minorities," The Los Angeles Times explains, "even the kingdom's critics do not want to overthrow the royal family. Instead they call for a gradual shift to a constitutional monarchy, a sentiment that all but saps the day of rage of its rage."

Love of the Monarchy: Appearing on CNBC, Saudi Prince Al-Waleed bin-Talal--an international investor and the nephew of Saudi Arabia's King Abdullah--called Saudi Arabia's day of rage a "tempest in a teacup" and suggested that the day instead be called a "day of allegiance and love for king," Business Insider reports.

In February, King Abdullah offered Saudis a package of about $36 billion in unemployment assistance, social security benefits, education subsidies, and housing loans, but has yet to show any willingness to grand political reforms.