By Desmond Walton

Erawan Shrine, the site of a bombing in Bangkok, Thailand on August 17, 2015. Source: pinelife’s flickr photostream, used under a creative commons license.

The horrific bombing in central Bangkok on August 17 was the worst attack ever suffered by the Thais and will likely have a 9/11-type impact on the country’s internal security policies. The attack is a huge setback, especially at this very delicate political time, when painstaking progress is being made towards crafting a new constitution and setting the timetable for elections.

No matter the culprit, Thai authorities will impose more stringent internal security measures, which will further exacerbate the government’s strained relationship with political groups and Thai citizens striving to influence the outcomes of ongoing debates about the political future of Thailand.

Let’s quickly review the most plausible scenarios behind the attack before more fully assessing the long-term impact. The full investigative weight of the Thai intelligence services, no doubt assisted by their American counterparts, will relentlessly examine every possible angle of this attack in the coming days. At this time, no one has claimed responsibility for the attack and we simply don’t know who did it. But there are some obvious starting points for the investigation.

First, is a scenario involving opponents of the current government. An attack perpetrated by political opponents would be aimed at undermining the legitimacy of the government and damaging the Thai economy. The opposition has been driven underground in the aftermath of the coup and we have not seen one centrally-controlled umbrella organization emerge to lead a counter-coup campaign. This attack would be a shocking change in the tactics surrounding the “normal” use of political violence in Thailand.

Second, is the possibility that Muslim separatists from Thailand’s three southernmost provinces have decided to expand their insurgency into the heart of the country. This would represent a major watershed, as the separatists until now have been content to confine their campaign to the south – or perhaps, incapable of conducting operations outside of their home turf. Insurgent attacks in Bangkok have long been viewed as the most dangerous course of action, portending a widening of the conflict that would have significant negative impact on Thailand’s stability and economy. Such attacks would also be an indicator that the homegrown southern insurgency has been infiltrated by global jihadists with more ambition and resources to expand the conflict.

Third, the attack could be the work of a lone wolf, self-radicalized, and perhaps with grievances not overtly political. This broad category ranges from a disgruntled employee of the Hyatt Erawan Hotel to someone with a perceived grievance against Thailand’s significant Indian population (though the majority are Sikh). Because at least three Chinese tourists were killed and more injured in the attack, there has been speculation that Uighur extremists seeking retribution for the recent forced repatriation of approximately 100 Uighurs to China were behind the attack.

No matter who the culprit was, one cannot overestimate the psychological impact of this murderous attack. It targeted ordinary Thais and tourists in one of the most iconic locations in Bangkok’s central shopping district. By contrast, the attacks associated with 2010 and 2014 political instability were smaller-scale and targeted at protest participants, security forces, or various courts and ministries located outside central Bangkok. The vast majority of Thais have grown accustomed to this low-level violence and view it as almost routine. But the Erawan Shrine is a place where parents take their children, where ordinary Thais go to make offerings and ask for blessings and good fortune. Thais know that the evil intent behind this attack at the end of a busy workday was to cause maximum casualties and shock value. It succeeded.

The attack has also left the Thai government shaken. Since the May 2014 coup, the government has battled to maintain its tenuous legitimacy and quickly quashed any emerging sign of dissent. Prime Minister Prayuth Chan-ocha is an old school, “law and order” leader who has framed the restrictions on civil liberties that he has imposed as an essential trade off to guarantee internal peace and stability. Most Thais, enthusiastically or begrudgingly, have accepted this arrangement. This attack has punctured the aura of safety and stability that the post-coup government has strived strenuously to instill.

The bomb blast will have significant negative impact on an already-weakened economy. The important tourism sector has proven resilient in the past, but this attack sets a new infamous benchmark that potential visitors will no doubt consider carefully before visiting Thailand. This is especially true for the huge Chinese segment of the tourist market (approximately 6 million Chinese visited Thailand in the first half of 2015). Pointing to a possible Uighur connection, some press reports out of China are already claiming that Chinese tourists were targeted in the attack.

Apart from tourism, the broader economy will be impacted as international investors weigh their investment decisions in light of Thailand’s protracted political instability and the terrible bombing. Thailand’s neighbors appear as increasingly attractive alternatives to investment in Thailand.

The outcome of this despicable event is predictable, especially if the investigation settles on political opposition as the perpetrators. Thai authorities will redouble their efforts to ensure internal stability. Whatever remaining latitude there is for political expression will be further and ruthlessly limited. Efforts to institutionalize extra-governmental oversight in the new constitution will be strengthened, as the threat posed by further political violence will be used as a bogeyman to make the case that an emergency snapback to authoritarian rule is a necessary precaution.

If the attack is pinned on southern Thai Muslims, the Thai military will take the gloves off and redouble its efforts to quash the insurgents. This strategy could well backfire if the military adopts a heavy-handed approach that exacerbates the underlying causes of separatist sentiment.

Regrettably, the attack will also reinforce Thailand’s obsession with internal security at the expense of engaging on regional and global issues. This has been an ongoing struggle since at least the 2006 coup. However, over the past 10 years during the times Thailand has felt confident to turn its attention from internal issues, it has proven time and again to be an essential regional partner. A further turn inwards prompted by the bombing will impose a cost on the region in terms of degraded Thai engagement on important regional issues such as ASEAN integration, human trafficking, and the South China Sea.

Colonel Desmond Walton was the U.S. defense attaché in Bangkok, Thailand, until June 2015. He previously served as the director for Southeast Asia in the National Security Council.