KUWAIT CITY: By sending a Saudi Arabian suicide bomber to Kuwait and recruiting local members of a stateless underclass to help him attack a Shia Muslim mosque, an Islamic State cell struck at the Gulf Arab monarchy's most potent internal divisions.
Relations have traditionally been good between the 70 per cent of Kuwait's 1.4 million citizens who are Sunni and the Shias who make up 30 per cent, but regional rivalry between Sunni Saudi Arabia and Shia Iran has opened some fissures.
The country, home to the region's most open Arab society, is also divided between descendants of its original townsfolk and those of Bedouin tribes, between extremists and liberals and between rich and poor.
For decades, Kuwait's ruling Al Sabah family has played the social, religious and political groupings off against each other, say critics, while side-lining injustices such as the plight of over 130,000 stateless "bidoon", meaning "without".
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Islamic State is adept at exploiting vulnerabilities with its violently puritanical message, a tactic it could use in other Gulf Arab states where despite great wealth, bitter inequalities persist.
But while many Kuwaitis say they hope the government will respond to this challenge by addressing internal problems and maintaining its open tradition, they fret it will instead follow the authoritarian lead of the biggest Gulf state, Saudi Arabia.
"Now there is a lot of fear after this action that the government will take more measures regarding more security, more limits of rights," said Mohammed al-Dallal, a former member of parliament with the Muslim Brotherhood-affiliated Islamic Constitutional Movement.
Friday's attack, which killed 27 and injured more than 200, put Kuwait on the front line of a extremist problem that has been aggravated in its neighbouring Iraq by the tussle for regional dominance between Saudi Arabia and Iran.
Kuwait is a rare island of open debate in the Gulf, with elected MPs who can challenge the ruling family's appointed government and a tradition of free debate that allows critics to publicly question both the state and regional heavyweights.
Tribesmen and Salafists
This diversity has carried a political price, as the Al Sabah dynasty has often taken advantage of splits to better maintain its rule, giving or withholding patronage to prevent any one group from growing powerful enough to threaten its primacy.
In recent years, seemingly urged on by Gulf allies, it has grown less tolerant of dissent, jailing citizens for tweets critical of the Al Sabah and changing electoral laws in ways critics say make it harder for the opposition to win a majority in parliament.
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What some fear is that the government will now become the last member of the Gulf Cooperation Council, which also includes Saudi Arabia, Qatar, Bahrain, the United Arab Emirates and Oman, to approve a security agreement that could limit rights.
Drive up the highway west out of Kuwait City, through plain suburbs and large open areas of scrub trees intersected by electricity pylons, and you pass first the bidoon area of Sulaibiya and eventually the tribal district of al-Jahra.
The houses are smaller and shabbier than in Kuwait's inner city where the scions of wealthy merchants, both Sunni and Shi'a, and the professional classes, make their lives.
Many bidoon are descendents of Bedouin nomads from inside Kuwait who failed to register with the authorities when its borders were set 50 years ago, while others are more recent undocumented migrants from Iraq seeking access to its riches.
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At least two of the suspects Kuwait has detained after Friday's attack are from this disenfranchised community, as was the Iraq-born father of Mohammed al-Emwazi, known in the West as Islamic State's beheader of hostages, Jihadi John.
"Islamic State will find some angry people because of some social issues. I think number one is the bidoon," said Dallal, describing the issue as a "time bomb".
Kuwait's Bedouin tribes, while much better off than the bidoon, have historically been looked down on by cityfolk, who often regarded them as unsophisticated, while they in turn often decried the cosmopolitan urbanites as irreligious.
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It was among these groups that Salafism, the ultra-strict strain of Sunni Islam native to Saudi Arabia, has thrived in Kuwait, with its sympathy for tribal traditions, its egalitarian approach to those within its fold and intolerance of Shiaism.
Fuhaid al-Humailan, spokesman for a Bedouin Salafi party, condemned Friday's bombing, but then quickly turned to what he described as the terrorism perpetrated by the West and Shia Iran against Arab Sunnis as representing Kuwait's main threat.