ISIL is adept at exploiting vulnerabilities with its violently puritanical message and call to an Islamist utopia
By sending a Saudi Arabian suicide bomber to Kuwait and recruiting local members of a stateless underclass to help him attack a Shi'ite Muslim mosque, an ISIL cell struck at the Gulf Arab monarchy's most potent internal divisions.
Relations have traditionally been good between the 70 percent of Kuwait's 1.4 million citizens who are Sunni and the Shi'ites who make up 30 percent, but regional rivalry between Sunni Saudi Arabia and Shi'ite Iran has opened some fissures.
The country, home to the region's most open Arab society, is also divided between descendents of its original townsfolk and those of Bedouin tribes, between Islamists 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 sidelining injustices such as the plight of over 130,000 stateless "bidoon", meaning "without".
ISIL is adept at exploiting vulnerabilities with its violently puritanical message and call to an Islamist utopia, 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 jihadist problem that has been aggravated in its neighbour 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.
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.
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 dowdy 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'ite, 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.
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 ISIL's beheader of hostages, Jihadi John.
"ISIL 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.
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 Shi'ism.
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 Shi'ite Iran against Arab Sunnis as representing Kuwait's main threat.
In the 1980s, the government encouraged Salafists as a counterweight to the Muslim Brotherhood and the movement has grown ever since, becoming a force that held many seats in the last parliament and has mobilised young people on the street.
Although the Muslim Brotherhood has held fundraising events for rebels in Syria, providing cash that the West believes may have gone to militants, it is Salafists whose ties to jihadist groups most worry Kuwaiti liberals and Shi'ites.
"Salafist extremism existed in Kuwait a long time ago. But the government gave us deaf ears. They didn't listen until this tragedy happens," said Ali al-Baghli, a liberal former oil minister at a diwaniya, as Kuwaitis call their nightly salons.
As Shi'ite victims were buried on Saturday, Kuwait's flag hung at half mast by the emir's seafront palace and condolences were heard in the Sunni Grand Mosque.
Shi'ites at the funeral, the men and women sipping thimbles of tea at the salon held at a liberal political society and Islamists in a Bedouin district outside Kuwait City all commended their ruler, Sheikh Sabah al-Ahmed al-Sabah, for visiting the bomb site within an hour of the attack.
Yet despite the emotional pledges of unity and allegiance, few people said they expected meaningful changes in how the Al Sabah handled the grievances ISIL exploited, and still fewer seemed to agree on what changes, if any, should be made.
I know the attack on a Mosque in Kuwait is 'old' news, however, I alsways wondered how the suicide bomber was able to fly from S Arabia into Kuwait and go staight to the Mosque and to carry out the attack. Should the bomb not have been dedected while passing security at the Airport??? In actual act at both Airports - at least that is the case when I travel in the various countries in the Gulf. There is a strict control when departing and again - not so strict - on arrival??