Given the neoliberal emphasis on breaking down barriers, why has the modern world increasingly turned to the seemingly anachronistic technology of built walls? The coeditors of Walling In and Walling Out bring together scholars of geography, archaeology, anthropology, and sociology to discuss this question. What connects their approaches—and elevates this collection beyond a catalog of carceral horror—is an intimate attention to the wall as a material thing. Although densely caught up in the theater of authority, walls are also material objects whose lives complicate and exceed the limited purview of both their intended function and symbolic aura.

The volume is organized into three sections, each framed around a different scale of wall. Following an introduction by Randall McGuire and Laura McAtackney that highlights their material approach to walls, McGuire offers a 10,000-year comparative history of wall building. He argues that whereas premodern walls were built to address threats of looting barbarians, contemporary walls are built to keep out and demonize refugees and other poor people seeking opportunity or succor. Although a compelling and provocative claim (and a productive distinction that orients the book), this is ultimately too easy and too simple a binary. As archaeologists are particularly aware, neither refugees nor “barbarians” are the exclusive property of any age.

Following McGuire's historical framing, Chapters 3 through 5 focus on walls built at the subnational level. Zaire Dinzey-Flores discusses neighborhood walls in Puerto Rico, comparing the lived experience of walls built around gated communities to those built around public housing. Dinzey-Flores argues that these neighborhood walls materialize and enforce social inequalities, in particular racial inequalities. McAtackney maps the effects of peace walls in contemporary Belfast, built by the British state during “the Troubles” to keep Catholic and Protestant communities apart. Serving as material impediments to community interaction and canvases for historical memorials, these peace walls reinscribe socioreligious divisions in the present while also memorializing a particular gendered and classist version of Belfast's history. Amahl Bishara looks at the effects of the Israeli-built wall on Palestinian life and resistance in the Aida Refugee Camp. Bishara argues that although the separation wall is an instrument of dispossession and the violent disruption of everyday life, physical resistance to the wall serves as a material locus for community identity and solidarity.

The second section scales up to the level of the nation-state. Anna McWilliams provides an archaeological exploration of the Berlin Wall as both material security technology and metaphor for the ideological battle of the Cold War. Mapping its physical remains, McWilliams looks at the places where these remains materialize a certain triumphalist vision of Cold War heritage, as well as places where this narrative is complicated and undermined. In his chapter on antimigrant border security in Greece, Demetris Papadopoulos suggests thinking of walls in a more distributed sense, highlighting how nonbuilt environments such as mountains and oceans are mobilized to function “as a wall” (p. 137). Papadopoulos compares the violent effects of walling out refugees on the island of Lesbos in 2015 with an earlier moment of walling out during the Greek Civil War (1946–1949) on the northern Greek border. Just as he seeks to de-emphasize a singular focus on the built wall, he also seeks to de-emphasize the present as an exceptional period of “bordering” (p. 136). Michael Dear compares the lived experience of the US/Mexico border wall with the perspective from Washington, DC. Dear argues that the borderland is its own community—a third nation between the US and Mexico—and one that is being torn apart (ultimately, unsuccessfully) by a violent and disruptive wall.

The final section extends and complicates prior analyses. Margaret Dorsey and Miguel Díaz-Barriga focus on the extensive security grid of computer algorithms, sensors, dogs, and checkpoints that support the US/Mexico border wall. More than simply a barrier impeding movement, the security grid produces confusion among border residents, ambiguous legal circumstances, and clandestine data collection. Starting with the first modern state borders in the seventeenth century—and the first maps drawn to represent these borders—Reece Jones argues that the contemporary florescence of border walls continues the symbolic work of mapmaking, using monumental solidity to exude claims about the natural boundedness of the nation-state. Beyond this symbolic comfort, border walls are highly ineffective at defending a country or stopping migration, but they are highly effective at destroying environments and making migration deadly. The book concludes with a short overarching summary that gathers shared arguments across the case studies.

The strength of this volume is its diversity of approaches. The rejection of an exclusive focus on border walls and the decision to include more local walls is especially well taken, although this emphasis could have gone further to discuss other types of walls (e.g., prisons). In general, as a project seeking to explain a global proliferation of walls driven by neoliberalism and fears of globalization, its selection of case studies is somewhat predictable and geographically limited to the peripheries of Europe and North America. The volume's argument that contemporary wall proliferation is a global phenomenon tied to neoliberalism would be more compelling with examples from a broader range of locales that reflect the global complexity of mobility and exclusion. For instance, there is a proliferation of anti-immigration border walls being built in South and Southeast Asia that would have complicated the volume's general framing of the Global North versus the Global South. Taken as a whole, Walling In and Walling Out is a timely and fascinating book. Its case studies serve as provocative explorations that push readers to think about walls in different ways.