Andrew Rosenberg’s Undesirable Immigrants is a cutting-edge work of International Relations (IR) scholarship, and it is deeply critical of the IR field. It is also a brave book written with much integrity and care for the topic, method, and intended audience. I am grateful to have been asked to review it, since I found it not just convincing, but stimulating and refreshing. I hope it is widely read and considered by IR scholars and anyone interested in international migration.

Rosenberg begins with the basic puzzle of international migration, that widespread political resistance to immigration exists as an exception to liberal capitalism’s commitment to global free movement of goods and ideas. He then very carefully demonstrates another dimension to this puzzle, the reality that even as immigration laws have become facially race-neutral around the world, their effects are still systematically uneven. In other words, people who originate in the Global South or in postcolonial states have far less freedom of mobility than people who tend to be perceived in immigrant receiving states as white.

Rosenberg then explains this disparity, which he calls an “underflow” of legal migration from the non-white world, using three related theories, which he grounds methodically using an impressive blend of historical analysis, post-colonial theory, and sophisticated quantitative models. First, he argues that the right to control borders has not always been a core aspect of state sovereignty, but rather was constructed alongside the modern nation-state. As the source of authority shifted to “the people” rather than a monarch, modern nation-states became concerned about the composition of their peoples. Thus, the idea of keeping out undesirable immigrants became a matter of nationalist concern. Second, Rosenberg explains how colonialism created an uneven world in which colonial powers drastically redistributed global wealth to themselves while simultaneously constructing colonial subjects as racially “other”, inferior, more prone to violence, and less capable of self-rule. These intertwined processes made the citizens of postcolonial states into undesirable immigrants in the minds of Global North publics, because of both their poverty and their perceived racial inferiority. Finally, and quite ambitiously, Rosenberg posits that constructed notions of sovereignty have placed postcolonial independent states under the “hegemony of the nation-state model”, which expects them to perform sovereignty to gain legitimacy in the eyes of the hegemonic powers (p. 223). This dynamic leads Global South states to enact harsh border control measures of their own.

Taken together, the three prongs of Rosenberg’s argument point very clearly to colonialism as the root of the persistent racial bias we see in international migration today. He concludes with the assertion that, without an acknowledgement of colonial history, there is little chance of understanding or resolving the damage colonialism has caused. Undesirable Immigrants is deeply critical of the field of IR for its general lack of attention to colonialism as a historical force that shaped the ongoing dynamics of international relations.

This book has so much to commend it, I can only briefly highlight its strengths in the space allotted. First and foremost is its centering of colonialism as a corrective to so much work in IR and Migration Studies that has overlooked that topic. I deeply appreciated how anti-colonial, postcolonial, and Third World Approaches to International Law scholarship informed the theoretical development of the book. I also was impressed by the care with which Rosenberg discussed the topics of race and racism, going to great lengths to explain why race is a social construction and racism is an ideology based on a belief in white supremacy. Building on this care, I was particularly thrilled by the diligence with which he developed thoughtful measures of tricky concepts that matched the theory, and did not reproduce or reify problematic racial categories in the quantitative portions of the book. For example, instead of using racial data to demonstrate the pattern of racial bias in immigration policy, he developed a complex “average ancestral distance” measure, to show that states tend to have restrictive reactions to the arrival of people whose time at which they share a common ancestor is further away (p. 155). He also shows how former colonial powers tend to particularly increase their restrictive policies when they get influxes of arrivals from the places they colonized. In these ways, Rosenberg walks the walk of someone who rejects race as anything other than a construct, but still wants to use data to demonstrate racism as an ideology functioning in the world.

At the same time, I wish the book had been organized to integrate the theoretical and quantitative components a bit more, because I think it would have flowed more logically to have the quantitative analysis interspersed alongside the theory it is testing. The book also sunk into some deep “inside baseball” at points, wading through debates about various schools of thought within IR that did not seem central to the argument. I also was surprised to find that after the opening vignette of the book, there were almost no specific examples provided of migration restrictions that look colorblind but have racially disparate impact. I know that IR is very focused on the big picture and large-scale trends, but more cases to sink one’s teeth into would have grounded this reader and better supported the argument.

While the book was very thoroughly researched, there were a few topics I wish Rosenberg had engaged with more. First is an exploration of law and legality in the analysis, particularly because the existence of facially neutral laws that have disparate impact is a central concern for the field of law and society. Similarly, I understand that the quantitative analysis could only cover legal immigration because that is what the data can measure systematically, but more exploration of the ways in which anxiety about unauthorized migration informs immigration policymaking would have enriched the discussion. Further, I am curious whether Rosenberg views his argument as compatible with the growing literature expanding James Hollifield’s concept of “the migration state” to include the Global South and postcolonial world (James Hollifield, “The Emerging Migration State,” International Migration Review 38[3]: 885–912 [2004]; see also Fiona B. Adamson, and Gerasimos Tsourapas, “The Migration State in the Global South: Nationalizing, Developmental, and Neoliberal Models of Migration Management,” International Migration Review 54[3], 853–882 [2020]; see also Kamal Sadiq, and Gerasimos Tsourapas, “The Postcolonial Migration State,” European Journal of International Relations 27[3], 884–912 [2021]). I would have also loved to see an engagement with the work of legal scholar E. Tendayi Achiume, who argues that contemporary migration is a form of decolonization (refer to “Migration as Decolonization,” Stanford Law Review 71 [2019]). Finally, while the book talks a lot about the development of the concept of sovereignty, and a lot about colonialism, I think it could have spent more time discussing how the concept of sovereignty was developed in service of the colonial project (Hamlin 2021).

I found the section of the book that develops a model to estimate the global migration “underflow” fascinating, but I wondered why Rosenberg chose the language he used to describe it. The baseline theoretical model includes “the important variables that should drive the migration between states” (p. 132). Rosenberg calls this baseline model an ideal world without racial bias, but economic inequality and war are still rampant. Rather than an ideal world, it seems to be estimating what migration would look like in a world without so-called national interest translated into law and policy. The comparison between this model and estimated actual migration numbers reveals that there is much less legal immigration than there would be if push and pull factors acted unobstructed by law (p. 133). So, I left this section wondering, is the baseline model just estimating migration in an open borders world? And if so, why did Rosenberg make the choice to not frame it that way? I think a more explicit discussion of what the model is imagining would have been really powerful.

Finally, I finished the book wondering how Rosenberg’s clear findings of culpability could be translated into a sense of obligation among the powerful. He argues that rich countries tend to “ascribe economic insecurity as a deserved status for those living in poor countries” (p. 202). This point seems key, as it highlights the ways in which former colonial powers continue to benefit from a total denial of the negative impacts of colonialism. It is because of this denial, and the depth with which the current state of affairs benefits the powerful, that I am not optimistic that sovereignty can be reconceived, even by an “exogenous shock” like climate change, as Rosenberg suggests (p. 283). We see how miserably the world has failed to respond with “cosmopolitan empathy” for fellow humans in need during the COVID-19 pandemic (p. 283). Thus, I am deeply skeptical that any form of migration “cooperation” between states could be free from the dynamics of “uneven sovereignties” (Hamlin 2021). As Rosenberg acknowledges, the concepts of national interest and national security have become convenient stand-ins for racism, and as I have argued, even the concept of the “refugee,” a supposed exception to the rule of sovereign border control, has been used in this way. Given how convincingly he establishes the entrenched roots of the current system, I would have liked to hear more about whether Rosenberg truly is optimistic about the potential for change.