Those displaced by such activities but who do not cross a border are classified as internally displaced people. A person crossing a border seeking refuge in another state may apply for protection in the territory, and such applicants are called asylum seekers. If the application is successful, the person’s legal status changes and they are recognized as an official refugee. Achieving formal legal status can come with certain rights and entitlements that are not afforded to asylum seekers, such as a right to work in the country of refuge.
In practice, the distinction between voluntary and involuntary migration can be rather arbitrary. Levels of coercion, in reality, fall along a continuum as migrants experience different forms of pressures that they perceive as forcing them to leave. One such huge category of pressure relates to economic conditions and opportunities in countries of origin. Many people who seek to leave their home countries are not successful in doing so lawfully. Often desperate people might feel compelled to take matters into their own hands, and they might seek to enter their desired destination state in ways that are characterized as “illegal,” “unauthorized,” “undocumented,” “irregular,” or “illegalized.” While many people have strong preferences as to which of these terms to use, I will refer to those who enter in such ways as undocumented migrants to adopt what I believe to be one of the most widely used and neutral ways of referring to members of the group.
Human trafficking involves the trade in people for purposes such as forced labor or commercial sexual exploitation. People smuggling differs from such practices in that the person being smuggled has consented to the transaction. While many cases of human smuggling may start off as consensual, the nature of the transaction may change considerably through coercive or exploitative elements, such as having to take out significant loans to repay the smugglers or others who facilitate international movement. Trafficked people are often held against their will and forced to work for the trafficker or their associates. In these situations, those trafficked can experience modern-day slavery.
1.2.2 Important drivers of migration
The factors that drive migration are sometimes categorized in terms of push and pull factors. Push factors repel migrants away from their countries of residence or origin, while pull factors attract them to a new destination. They can often be combined; for instance, a lack of economic opportunities in one area and better prospects for economic flourishing elsewhere provide a combination of push and pull factors that can motivate movement. Let us look at four large categories of reasons next, which can often be connected as well as distinct.
First, global inequality and uneven development drive much migration. Many popular migration corridors are from less developed to more developed countries, in which prospects for work and higher incomes are more abundant.
Second, demographic changes can underlie much movement. Some countries have high birth rates and young populations. Others have low birth rates and aging populations. One challenge for countries with high birth rates is to provide employment opportunities for all its citizens. Migration for work provides a good fit for both those countries with surplus labor and those with higher demands for labor. For instance, an aging population creates high needs in service and care sectors in some countries, as is the case in Japan and many European states. And youthful unemployed workers in other countries might value the opportunities to work abroad rather than remain unemployed or underemployed at home.
A third set of reasons relates to challenges presented by conflict or political instability. Much migration in this category is undertaken to avoid war, violence, conflict, human rights violations, and other public crises that challenge the state’s capacities to its limits.
And finally, social, cultural, and political factors can drive much migration. Examples include a desire for more freedom to pursue religious goals or to seek lifestyle, social, or cultural opportunities that are restricted or not available in the home country.
1.2.3 Some central general economic impacts
Economists commonly cite the tremendous benefits of human migration today, such as migrants having increased the size of the world economy and contributed very positively to global GDP, higher incomes, and productivity. Remittances – the money sent back by migrants to family and friends in the country of origin – are another huge source of revenue. This flow of revenue can be of great value both to those who receive remittances and to the local economies of recipients.
International migration can also prove to be a potent catalyst for significant social, economic, demographic, and political changes in sending and receiving countries. Migrants can make significant sociocultural, political, and economic contributions both in the countries they join and those they leave, especially when they act as agents of change. One widely noted feature is that immigrants tend to engage in much higher levels of entrepreneurial activity compared to their native counterparts, perhaps because they have become used to taking greater risks. In some countries, such as the United States, migrants have made huge contributions to innovation (IOM 2020: 6).
While it should be acknowledged that there can be these significant general benefits, it is also important to appreciate that the effects of migration differ enormously among countries. Specific effects for particular countries can vary a great deal depending on who is migrating, where they are going, where they have been, and particular contextual factors such as government policies in home and host states. In various situations, migrants can affect labor markets, wages, prices of goods and services, economic growth, tax revenues, capital investments, health and educational outcomes, among many other factors. For instance, high levels of skilled migrants can lead to a brain drain from their country of origin but they can also raise the return on investment in education, thus leading to a higher education level among the remaining population. This phenomenon is called brain gain, though to what extent the phenomenon exists in certain countries and particular sectors also varies considerably. Skilled emigrant diaspora populations can also contribute positively through remittances and political and economic channels. In addition, returning migrants can bring with them capital and progressive ideas that can help reform the local economy and advance more democratic regimes through changes in political climate and public opinion. Whether or not these effects have measurable impacts and whether they outweigh several categories of disadvantages of migration, such as reduced health outcomes, declining wages, weakened institutions, or increased political instability, is another important issue. Such topics are discussed in more detail elsewhere in the book, such as in chapter 8.
1.3 Is the contemporary state of affairs unique? Some history
The history of human migration is vast, complex, and fascinating. Here there is space to highlight only a few seminal migration moments from that history.
Humans have been moving about our planet since the origin of our species, as people began occupying all the regions of our world (Scarre 2013a). Homo erectus began moving out of Africa across Eurasia about 1.75 million years ago (Mithen 1996). Homo sapiens occupied Africa about 150,000 years ago and had spread to all habitable parts of Australia, Asia, and Europe by 40,000 years ago (Dunbar 2004; Scarre 2013a). Many factors motivated early humans to migrate, including climate change and the search for more adequate food supplies.
Since the Neolithic period (roughly 12,000 years ago), most migrations involved aggression, such as conquest and colonization (Scarre 2013a). Colonialism, which began intensifying about 500 years ago, involved the expansion of settled populations, largely from Europe. European colonialism accelerated the pace of migration. New settlers sometimes overwhelmed and virtually eradicated local populations.
There has been much human migration
