London ( CNN ) Tunisia 's ultra-radical fringe has come back to bite a government born out of the most successful experiment in constitutional reform to emerge from the 2011 Arab Spring revolutions . Wednesday 's attack on the Bardo Museum in Tunis was grimly predictable , coming from what the Tunisian Interior Ministry calls a violent ultra-radical Islamist fringe forced underground -- but not crushed -- by security services . Jihadist firebrands representing thousands of active militants at home and abroad have been threatening retribution on Tunisia 's outward-looking , investment-friendly majority . The attack was carried out by two gunmen , believed to have been supported by at least two accomplices . It may torpedo efforts to revive Tunisia 's employment-generating tourism industry and may discourage other big-spending visitors . It will probably lead Tunisians -- who have shown a sage propensity to unite in the face of greatest adversity despite a marked appetite for political bickering -- to support a robust response by elected President Beji Caid Essebsi . The attack adds to the global narrative by which Islamic revolutionaries -- increasingly flying under the flag of the so-called Islamic State ( ISIS ) -- pose an existential crisis to moderate states , often Western allies , in the Arab world . Tunisia is the sole country to have emerged from an Arab Spring revolution with its political process intact -- current president , Essebsi , who was elected in November 2014 , and his ruling coalition , are the products of a long constitutional process . In four tumultuous years they have competed hard with , but also showed a capacity to work with , opposition parties , led by the `` moderate Islamist '' Ennahda , which is represented in government and parliament . Islamists of a very different hue were responsible for the Bardo attack . Local Salafist groups ( of whom the best known is Ansar Al-Sharia ) as well as multinational units including ISIS have been most effective in recruiting disaffected young Tunisians in the capital 's poorer quarters and in dusty towns of the south and interior , where the original revolution that removed Ben Ali in February 2011 surged up . Legitimate claims for more jobs and resources in these underprivileged areas during the four subsequent years have largely come to nothing , adding to frustrations . Radical jihadists -- some with back bases in Libya and Algeria -- have posed a major security challenge to successive governments , murdering two prominent `` secular '' politicians in 2013 . The Tunisian armed forces , supported by Algeria 's more experienced and better equipped military , have been fighting jihadist radicals in the Mount Chaambi region for nearly three years . They have yet to declare final victory , pointing to the resilience of underground groups . While successive governments have acted against radical Salafist groups , thousands of Tunisians have gone underground ; they are widely believed to make up the biggest national group fighting with jihadists in Syria ( over 3,000 by many accounts ) , and are present in Libya and other failing states . In January 2013 , Tunisians and Libyans made up the majority of jihadists who attacked a strategic gas plant operated by BP and Statoil in southern Algeria . So , the Bardo attackers are a known enemy . Prime Minister Habib Essid has promised a robust security response . But the Tunis tragedy is unlikely to have any immediate impact on the political process . A majority of Tunisians remain foursquare behind preserving `` republican institutions , '' even if they vocally disagree on the detail of policy . It will remind Tunisia 's many friends that the country 's transition is brittle , and that Tunis needs commitments of support to become reality , with more military and wider financial assistance , and , above all , investment that can kickstart an economy in the doldrums since 2011 . Massacre at the Bardo places Tunisia more centrally within the global ISIS narrative , which has recently expanded to neighboring Libya . It is a ghastly way to remind the world that Tunisia 's experiment in democratic reform needs all the help it can get .
Jon Marks : Ultra-radical fringe has previously threatened CNN 's liberal majority . Majority of CNNns likely to support robust response from president , he writes . Attacks a reminder that CNN 's transition to democracy is `` brittle , '' Marks says .