It was a stark warning delivered at the height of the battle for Aleppo: Michel Kilo, a prominent Syrian dissident, told Saudi Arabia that the blowback of meddling in his country would be simple. "This havoc will eventually end up destroying them," he said, referring to the Saudis.
"If events in our country do not come to an end, [the terrorists] will move towards them in groups. Eventually they will see what’s coming for them,” Kilo said.
Kilo's warning plays into what many in the Gulf might fear: that Saudi and Gulf Cooperation Council (GCC) support for the rebels fighting Syria's president Bashar al-Assad has prolonged the war and will have unintended consequences. The Gulf could face an influx of militants as groups such as the Islamic State (IS) and the Al-Nusra Front are defeated on the battlegrounds of Iraq and Syria.
According to the Soufan Group, an intelligence service, there are 2,500 Saudis fighting for such groups, the highest total from the Gulf states. In contrast, there are only an estimated 70 Kuwaitis doing the same thing.
But there is already a threat within the Gulf states' own borders, with IS claiming, and being blamed for, a string of attacks in Saudi Arabia and beyond. According to counter-terrorism expert Mustapha Alani from the Gulf Research Centre, a think tank, Saudi Arabia has arrested 500 people with links to IS since 2014, but attacks still get through.
In October, Saudi Arabia arrested four people in the province of Shaqra for what it said was a plot to attack the Al-Jawhara football stadium during a match between Saudi Arabia and the UAE and taking orders from IS in Syria. The month before that, 17 people were arrested for coordinating with IS and planning attacks on civilians against security personnel and government sites.
In July, three suicide attacks targeted the Saudi cities of Jeddah, Qatif and Medina. In Jeddah, a Pakistani expatriate injured two security officers in an attack on the US consulate. A Shia mosque was targeted in Qatif. In Medina, the bombing targeted a security office next to the Prophet's Mosque. No group has claimed responsibility for the attacks, but suspicion, as ever, falls on IS.
In Kuwait, meanwhile, an IS network was broken up in July, a year after the group killed 27 people in a suicide attack on a Shia Muslim mosque.
IS may now be able to play on deep-rooted issues dividing the Gulf countries, including the sectarianism that has torn apart countries such as Iraq and Syria. The organisation has targeted Shia sites in Qatif in Saudi Arabia's oil-rich Eastern Province, for example, where the majority of the country’s Shia population resides.
Kuwait faces a similar threat as up to 30 per cent of its population are Shia Muslims, who up until now have maintained relatively good relations with the country's majority Sunnis.
The Qatif attacks fall within the divisive narrative boasted of by Abu Mussaab al-Zarqawi, the leader of IS in its formative years in Iraq, who vowed to use attacks on Shia Muslims to elevate the organisation's stance among Sunnis in Iraq, a strategy to which Al-Qaeda’s leader Ayman al-Zawahiri objected.
Militant networks in the Gulf are, however, unsophisticated. According to Alani, while IS lacks a "real structure" in Saudi Arabia, small cells and individuals still operate inside the country.
"The cells are generally comprised of two to three people, but for the most part IS relies more on individuals we call 'door-knockers'," he said, in a reference to lone-wolf attackers.
These are not Saudis tested on the battlefield and sent by IS back to their home country. Instead, they are generally poorly trained amateurs, explaining the often poor execution of most attacks in Saudi Arabia.
"These militants are for the most part uneducated, socially isolated, and looking for a purpose," Alani said.
Few recruits:Recruitment numbers have been low, despite the prominence of Saudi militant figures in Syria, such as IS's Turki Binali and sheikh Abdel-Aziz Qatary, the founder of the Jund al-Aqsa group which recently merged with the Al-Nusra Front.
IS has generally failed to appeal to young Gulf nationals as its Saudi-led forerunner Al-Qaeda did in the past. "This may be explained by the fact that unlike Al-Qaeda, which was dominated by Saudis, IS is ruled by Iraqis and Jordanians," Alani commented.
IS's infamous social media presence has also dropped significantly in recent months as the IS "caliphate" has shrunk in Syria and Iraq and its enemies are pursuing a new "cyber-war" against the group.
Abdulkhaliq Abdulla, an Emirati researcher who specialises in Gulf affairs, said that all this may account for the organisation's continuing low profile in the Gulf countries. "IS appeals to Muslims in the Gulf dreaming of an Islamic revival. However, the more the ‘caliphate’ loses ground the less potent it is and the less it can appeal to the imagination," he said.
What of the Saudi money referred to by Kilo? Saudi Arabia has been repeatedly accused of supporting IS in Iraq and Syria. In October, a leaked email from former US secretary of state Hillary Clinton claimed that figures within Saudi Arabia and Qatar had supported IS and other groups.
"We need to use our diplomatic and more traditional intelligence assets to bring pressure on the governments of Qatar and Saudi Arabia, which are providing clandestine financial and logistic support to [IS] and other radical Sunni groups in the region," the document said.
Saudi Arabia also finds itself in a dilemma as IS is inspired by the brand of Wahabi Islam that prevails in the kingdom. However, Saudi Arabia and its allies have repeatedly denied directly funding and supporting IS and similar groups, and US officials state that what money is funnelled to the battleground comes from private "angel investors".
IS has also repeatedly rejected the legitimacy of the ruling Saud family in Saudi Arabia. "The organisation argues that Saudi Arabia is pro-western and does not represent true Sunni Islam," said Jordanian commentator Hassan Abu Haniya.
Indeed, Abu Bakr al-Baghdadi, the self-styled “caliph” of IS, has threatened Saudi Arabia in several speeches, the latest in November, and IS has declared several wilayat, or provinces, there, including Najd and Hijaz.
Al-Baghdadi has told his followers to launch “attack after attack” in Saudi Arabia, as a result of the Saudis "siding with the infidel nations in the war on Islam and the Sunna [Sunni Muslims] in Iraq and Syria."
Another trend in the Gulf may also embolden IS recruitment as the region is facing a debilitating economic crisis. Security sources speaking on condition of anonymity have said that Saudi Arabia has been witnessing unprecedented capital outflows, with members of the royal family and large merchant families taking their money out of the country.
Saudi Arabia's last budget showed a US$98 billion deficit. In response, Riyadh cut ministers' salaries by 20 per cent and said it would scale back by 15 per cent financial perks for members of its governing Shura Council and public-sector employees.
Saudi king Salman recently admitted that the economic policies were "painful," but he said they were necessary to secure the country's future in difficult conditions.
While Saudi Arabia and the wider Gulf region appear to have kept a lid on the current militant threats, the future beyond IS may be different, Abu Haniya commented. "The decline in the social contract across the Gulf region as well as political militantism might be a contributing factor for people to join terror organisations in the future," he said.
The writer is a researcher on Middle Eastern politics and a non-resident fellow at the Atlantic Council, a US think tank.