When it comes to the politics of immigration in America, is demography destiny? Maybe—but not yet, Tom K. Wong argues in this data-rich study of recent immigration politics in the United States. Earlier research on immigration politics generally highlighted the power of pro-immigrant and ethnic lobbies over diffuse mass preferences and charted the historical course of immigration policy through evolving institutional structures of opportunity (e.g., Gary P. Freeman, “Modes of Immigration Politics in Liberal Democratic States,” International Migration Review, 29(4), 1995; Daniel Tichenor, Dividing Lines: The Politics of Immigration Control in America, 2002). Wong sees these dynamics as still important but argues that partisan polarization and the votes and activism of immigrants themselves have become crucial parts of the story. The most important contribution of The Politics of Immigration is to theorize and empirically test the impact of these factors on congressional voting and legislative representation.

The empirical meat is in Chapter 3, which analyzes several years of recent roll-call votes on immigration bills in the House of Representatives and the Senate. The evidence attests to the entrenchment of stark partisan divides, especially in the House, and the impact of foreign-born constituencies on pro-immigrant voting. While growing immigrant populations favor policy liberalization, this effect is blunted by the skewed geographic distribution of immigrants across districts and states. Wong also argues that the “electoral connection” weakens responsiveness to immigrants’ pro-immigrant preferences because many immigrant noncitizens cannot vote.

To zero in on this dynamic, Wong examines the effect on roll-call votes of districts’ and states’ noncitizen populations and naturalized populations in separate statistical models. Here, however, a measurement choice makes the results hard to interpret. Instead of comparing the effects of a district’s or state’s naturalized and non-naturalized foreign-born shares of the total population, Wong appears to compare, in separate models, the effects of the naturalized and non-naturalized shares of the foreign-born population. It is not clear why this is an appropriate metric: One would surely expect more electoral pressure from immigrants to be felt in a district with a very large foreign-born population, only a minority of which is naturalized, than in a district with a tiny foreign-born population, the great majority of which is naturalized. Although the relationships in the House roll-call votes work out as hypothesized, this issue may help account for the lack of corroboration in the Senate results. It also yields redundancy in the exposition of results, as the key entries in successive tables (3.3 and 3.4, with minor discrepancies in 3.7 and 3.8, and some appendix tables) and columns (Table 3.5) are additive inverses of one another (because the naturalized share of the foreign-born population is one minus the non-naturalized share). In an analysis this ambitious, there are bound to be some mistakes. Fortunately, the problem pertains only to a subsidiary argument and does not seriously weaken the book’s major claims.

The fourth chapter further probes immigrant representation with two field experiments designed to ascertain whether representatives treat undocumented residents of their districts as constituents. Wong and his associates Michael Nicholson and Nazita Lajevardi generated emails to House representatives in which the ostensible ethnicity and legal status (undocumented immigrant versus U.S. citizen) of hypothetical constituents from the representative’s own district were varied at random. The emails in the first experiment solicited a meeting with the representative, while the emails in the second requested clarification of the representative’s position on whether illegal immigrants should be offered a way to become U.S. citizens. The first experiment finds clear evidence that illegal immigrants are less likely to secure a meeting with their representative than are U.S. citizens. The second experiment finds a surprisingly modest and insignificant difference between representatives’ propensity to articulate their policy position in response to queries from undocumented immigrants and citizens. Neither experiment has sufficient power to yield clear inferences about whether racial bias or undocumented legal status is the active ingredient. To speculate, representatives may widely perceive some obligation to provide information (and possibly other forms of constituent service) to undocumented residents but feel less pressured to hear out their views than than those of citizens. The experiments reinforce Wong’s contention that barriers to citizenship and the franchise work against simple formulations of the demography-as-destiny thesis.

In his concluding chapter, Wong simulates future votes on hypothetical comprehensive immigration reform bills on the basis of estimates reported in Chapter 3. Notwithstanding strong assumptions about the growth of the foreign-born population, the evolution of its issue preferences and political power, and party alignments decades hence, the exercise paints a sobering picture of the prospects for addressing an immigration system that the great majority of Americans believe is “broken.”

The Politics of Immigration raises intriguing questions for future research. First and foremost, why has immigration become such a partisan issue and policymaking so susceptible to grassroots activism after decades of relative insulation from popular pressure? Wong sees the mass immigrant protests of 2006 as a watershed moment that galvanized immigrants and their allies, engendered a formidable right-wing backlash, and forced representatives on both sides to listen to energized constituencies. But without analysis of how congressional voting has changed over time, this claim is hard to assess. It conflicts with James Gimpel and James Edwards’ analysis that revealed heightened partisan polarization on immigration long before the mid-2000s, a trend they traced to the framing of immigration in fiscal terms (see The Congressional Politics of Immigration Reform [1999]). Wong expresses skepticism about this explanation. He contends that positions on immigration are related to the “inviolability” of American national identity, but it is not clear exactly what this means beyond insistence on citizenship as the bar for full political membership. His assertion that the contemporary status of undocumented immigrants is heir to the country’s historic racial restrictions on citizenship, and his characterization of a record of voting against expansionary immigration policy as a failure to “embrace diversity” (e.g. pp. 192, 208, 218–19), are political statements with which one can easily disagree.

Second, do Wong’s insights about congressional voting on immigration apply to the politics of immigration in the U.S. generally? The heavy reliance on nonunanimous roll-call votes, beyond a few ad hoc discussions of bill sponsorship in Chapter 2, raises questions about the degree to which more consensual or less publicly visible immigration issues defy the book’s theoretical framework. Expanding the analysis beyond congressional voting might strengthen as well as qualify Wong’s case regarding the centrality of partisanship. President Barack Obama’s executive actions on immigration were spurred by more intense pressure from immigrant rights lobbies and met with more extreme partisan polarization than those of his predecessors. Subnational immigration politics is also a highly partisan arena, as Wong and colleagues have shown elsewhere (Karthick S. Ramakrishnan and Tom K.Wong, “Partisanship, Not Spanish: Explaining Municipal Ordinances Affecting Undocumented Immigrants,” in Monica Varsanyi, ed., Taking Local Control: Immigration Policy Activism in U.S. States and Cities [2010]). On the other hand, bipartisan consensus on important aspects of immigration might lurk beyond the voting record. It remains to be seen, for example, whether Congress will ever vote on the recent bill sponsored by Senators Tom Cotton and David Perdue and backed by President Donald Trump, which would drastically cut legal immigration and instate a skill- and language-based “points system” in place of thousands of family-based visas. Certainly the initial reception, including among many leading Republicans, has been icy.

In sum, Wong offers an important explanation of how partisanship and demographic change influence efforts to reform immigration policy. In addition, his detailed and insightful discussion of the major immigration controversies of our era makes The Politics of Immigration an excellent resource for those who wish to learn more about the multiple dimensions of contemporary immigration debates.