The arrest of an alleged al-Qaida cell in the United Arab Emirates and of 94 citizens accused of "security offenses" illustrates the alarm sweeping the Persian Gulf monarchies as the wave of Arab pro-democracy uprisings reaches their door.

The arrests in the Emirates, along with a widening crackdown on dissent, shows how Western-backed absolute rulers are shuddering at the prospect of infiltration by Islamic militants bent on bringing them down.

Royal families in Saudi Arabia, Kuwait and Bahrain are all, to one degree or another, grappling with rising dissent and demands for democratic reforms that will limit their power and authority.

The response of the ruling families has been to impose harsher punishments for dissent and boost cooperation between their powerful intelligence and security services.

They want, above all else, to head off the uprisings like those that since January 2011 have toppled four longtime Arab dictators -- the presidents of Tunisia, Egypt, Libya and Yemen -- and threaten President Bashar Assad of Syria.

Assad has particular significance in this swelling tide of revolution because he's the only republican leader to have inherited power from his father. He became president when his much-feared father, Hafez, and founder of the Assad dynasty, died in June 2000 after 30 years in power.

The ousted republican leaders of Egypt, Libya and Yemen had all sought to ensure that their sons succeeded them, which was one reason why their regimes were torn down by mass uprisings.

The gulf states are all monarchies run by desert clans who have for decades silenced dissent, whether political, religious or tribal, by using their vast oil and natural gas wealth to buy off opponents.

The six Arab states along the western shore of the gulf form the Gulf Cooperation Council, an alliance of desert dynasties who rule what are essentially police states. They're also traditional allies of the West, which tolerate them because of their oil and immense wealth.

Major upheavals that usurp the monarchies or entail political gains by militant Islamists exploiting the unrest could have profound consequences for a region that contains around one-fifth of the planet's hydrocarbons.

The only other surviving Arab monarchies are in Jordan, where the Hashemite throne is looking increasingly shaky as King Abdullah II drags his feet on long-promised reform, and in Morocco at the other end of the Mediterranean.

Kuwait, which has been a quasi-democracy since the ruling Sabah dynasty created a 50-member Parliament in 1963, the only one in the Arab gulf, is now at the center of this growing confrontation.

The oil-rich emirate, liberated by a U.S.-led coalition in 1991 from Iraqi conquest, has for months been rocked by large street protests against efforts by the emir, Sheik Sabah al-Ahmad al-Sabah, to arbitrarily revise electoral districts to ensure a tame Parliament.

The most prominent symbol of the unrest is opposition leader Musallem al-Barrak, a former lawmaker sentenced to five years' imprisonment April 15 for defying the emir's autocratic ambitions and state pressure to silence him.

Barrak, in whose name protesters now daily face police firing tear gas in the streets, was granted bail Monday. His defiance of Kuwait's rulers and their efforts to crush dissent embody the wider challenge to the established and traditional political order across the Arabian Peninsula.

"I am mesmerized by the continuing political developments in Kuwait -- and to a lesser extent in the other GCC countries -- where thousands of citizens of a wealthy, paternalistic and generous oil-producing gulf country continue to protest against the government for reasons anchored in rights rather than material needs," wrote Jordanian political commentator Rami G. Khouri.

"Kuwaitis raise the prospect of a movement toward becoming the first gulf oil-producing Arab state where the executive authority and police powers of the ruling family are checked by citizen-based accountability ...

"We are witnessing in Kuwait an unprecedented situation of anti-autocracy, mass civil disobedience by elements of a population that is not poor, hungry or lacking in basic services," Khouri observed.

"Unlike Tunisia, Egypt, Libya and Syria, these protesters are not demanding the overthrow of the regime.

"Rather, they are seeking constitutional reforms that give citizens basic rights to participate in decision-making and hold power accountable."