Just over a decade ago Illicit: How Smugglers, Traffickers and Copycats are Hijacking the Global Economy, hit bookshops around the world. Written by the then editor of Foreign Policy and former Venezuelan Minister of Trade and Industry Dr Moises Naim, Illicit outlined how the 'black' economy risked undermining the regulated economy, reshaping politics to the detriment of societies and destroying lives around the world.

Illicit received widespread praise for its thoroughness and accessibility. Some reviewers, however, suggested that Naim had overstated the impact illicit actors were having on states' abilities to regulate the movement of goods and people. Other reviewers commended him for persuasively arguing that illicit trade patterns threaten 'the very fabric of society' itself.

Ten years on from Illicit, what has changed? Have responses been effective or is the threat Naim outlined still present?

Naim's book covered illicit industries ranging from small-arms trading to illegal drugs to money laundering, but this column focuses on one area: migrant smuggling. Back in 2005, Naim argued that smuggling and its more sinister manifestation, human trafficking, were both growing illicit trades. He cited UN estimates that the combined business in smuggling and trafficking was worth US$7-10 billion annually.

Today, there is little doubt that migrant smuggling continues to pose many challenges, including for migrants risking death and exploitation during their journeys, and for states seeking to manage their borders. The patchy data available on smuggling indicate the number of people being smuggled around the world appears to be increasing overall, albeit unevenly geographically. It also seems that an increasing number of illicit actors are making considerable profits from that exploitation. Some estimate that up to US$1 billion was paid to smugglers along the Mediterranean Sea route alone in 2014.

The latest EU data show that 2014 saw a massive increase in illegal cross-border detections, most notably by sea across the Mediterranean, with almost 100,000 people being smuggled by sea between July and October alone. The use of cargo ships to smuggle on a larger scale in the Mediterranean, such as the recent Ezadeen ghost ship abandoned at sea by its crew, is an ominous sign that migrant smugglers are reaching a new scale of operational capacity.

African-based analysts have found that while the true scale of regional smuggling and irregular movement is difficult to quantify, the smuggling route to Europe via Libya continues to grow. They have also highlighted that in Libya migrant smuggling is directly linked to the smuggling of drugs and weapons, placing asylum seekers and refugees in the hands of criminal gangs.

US Border Patrol data stretching back several decades shows a big drop in illegal migrant apprehensions across the Southwest border with Mexico from the onset of the global financial crisis in 2007, however last year saw smugglers fill a soft market with extremely vulnerable migrants from Central America. The number of unaccompanied minors and families with minors who were apprehended in FY 2013–14 almost tripled to around 135,000, undoubtedly sending a collective chill through the spines of policy makers, international organisations and migrants' rights groups worldwide.

Closer to home, some of the largest migrant smuggling routes are thought to be in Southeast Asia, particularly between Indonesia and Malaysia. Analysts estimate the illegal migrant population in Malaysia to be around 2.2 million, with more than half from Indonesia.

Smuggling of asylum seekers to Australia is now in abeyance, at a time when factors enabling smuggling — modern transportation and communication networks; the growing prevalence of opportunistic unregulated actors — have perhaps never been greater. The current policy and operational framework in Australia has halted maritime migrant smuggling, but it is fragile in the face of such global forces, and it has come at a substantial cost.

Ten years on from Illicit and it's difficult to say whether the 'very fabric of society' has been irreparably harmed, though some communities in some societies have experienced just that. What is clear is that few inroads have been made in eradicating human smuggling globally in a substantive and sustainable way. There are at least three main reasons.

Firstly, there remain significant gaps in our understanding of migrant smuggling. Patchy data indicate that some smuggling routes are closely monitored while others are not; some smuggling routes have been effectively shut down while others appear to be flourishing. Improved data collection and targeted research is enhancing our understanding of smuggling but we still don't know the true scale and nature of many smuggling networks. We have a limited understanding of how inter-connected smuggling is with other forms of illicit activity; we may not yet appreciate the level of danger and insecurity experienced by those being smuggled.

Secondly, it is clear that while migrant smuggling is big business and multiple factors underpin the phenomenon (including poverty and relative deprivation), we are now in the midst of the largest episode of human displacement due to war, conflict and persecution seen for two decades. This has a direct effect on smuggling. EU data show that Syrians currently make up the majority of those intercepted in the Mediterranean Sea. Greater support of countries hosting refugees, realising the end of conflict in places such as Syria, and expanding durable solutions to displacement are all high global priorities.

Finally, a transnational problem requires transnational solutions involving multiple sectors and stakeholders that complement national initiatives. Policies, practices and operational responses that can account for international smuggling patterns, industry-specific labour needs and better industry regulation, international monetary flows, migrants' rights and motivations, as well as transnational linkages, have a greater chance of reducing migrant smuggling, securing borders and enhancing protection. There remains much work to be done.