Migration is overall not a source of terrorism according to new research from the University of Warwick.
In fact the study indicates that more migration could create a decrease in the number of terrorist attacks, not an increase.
The research was designed to establish whether migration helps spread terror attacks between countries. The lead author, Vincenzo Bove, associate professor in the University's department of politics and international studies (PAIS) said: "Our findings shouldn't be surprising. When migrants move from one country to another they take new skills, knowledge and perspectives. These stimulate technological innovation and diffusion of new ideas and this in turn stimulates economic growth.
"If we subscribe to the belief that economic development is linked to a decrease in extremism then we should expect an increase in migration to have a positive effect."
The study Does Immigration Induce Terrorism? has been published in the Journal of Politics. It is based on the analysis of terrorism in and migration flows between 145 countries between 1970 and 2000. Dr Bove and his fellow author, Tobias Böhmelt from the University of Essex and the ETH Zürich, measured the average number of terror attacks stemming from countries in a given year, taking into consideration the level of migration as a "link" between states.
The academics measured the level of risk using data on migration inflows from the World Bank, weighted by the number of terrorist attacks in the country of origin of the immigrants.
They ascertained that the countries with the highest level of exposure to the diffusion of terrorism are those with many migrants from regions with a high number of terrorism incidents such as India, Pakistan, Morocco, Western Sahara, and Tunisia. They also determined that in 2000 countries such as Finland, Sweden, Italy, Bolivia and Paraguay had very low risks. They found that this measure of exposure is positively and significantly associated to the actual level of terrorism "at home".
Dr Bove and his researchers noted that patterns can change over time. He said: "This is one example as our study looks at the period 1970-2000. Every year the risk of terrorism diffusion in each country varies, as a result of new migrations waves and changing levels of terror in the country of origin of the migrants."
They found that migration can under some specific circumstances be a vehicle for and driver of terrorism. The researchers detected that there was an increase in terrorism in a country that accepted migrants from another where terrorism is rife. However, countries, which accepted immigrants from countries where there is no or a low level of activism, did not suffer exposure to terrorism.
The research paper also indicates that extremism could spread from countries with high incidences of terrorism at a macro or micro level. At a macro level, terrorists can exploit ties among a migrant group's members through radicalisation. At a micro level, migrants may bring to their new country expertise in terrorist skills and tactics, which they could pass onto individual terrorists in the host country.
The research highlights that whereas terrorism can travel from one country to another via migration flows, only a very small minority of migrants from high-terrorism states can be associated with increases in terrorism, and very often in an indirect way. Dr Bove said: "Terrorist organisations often exploit migrant networks and migrant communities as a recruitment pool.
"Therefore, even the enforcement of discriminate immigration laws on immigration from terror-prone states is not advisable if national security agencies and immigration authorities fail to identify the organisers of terrorism in the first place. "We hope that policymakers will not enforce immigration laws in an indiscriminate way as this may lead to the loss of the positive impact of migration."
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Does Immigration Induce Terrorism? Journal of Politics. DOI: 10.1086/684679