The second night of the Republican National Convention had the theme of “Making America Safe Again.” As Texas Senator Ted Cruz proclaimed, “your family is less safe, your children are less safe, the country is less safe” — all because of Joe Biden’s presidency. While crime was the central focus of the night’s speeches, immigration loomed large in the messaging as well.

The GOP platform not only adopted Donald Trump’s hardline stance on the topic, it spelled out purported links between immigration and crime, terrorism, and the opioid crisis. Trump hammered home these ties during his acceptance speech. 

Republicans claim that the way to fix all of these problems is the largest mass deportation program in American history, requiring localities to cooperate with federal immigration enforcement, and securing the southern border. While the Democrats have shied away from these extreme positions, they too have latched onto immigration to appeal to voters concerned about border security, crime, and safety.

This messaging is finding particular resonance in America’s suburbs. While the suburbs haven’t been as much of a focus in the media as in past campaigns, they matter more than ever. As of 2020, 54% of Americans lived in suburban areas. They may well hold the balance of power in November, not just in the presidential race, but especially in determining control of the House of Representatives.

The suburbs have their own political culture, one that’s often protectionist on local matters — built around the desire to safeguard and defend homes and neighborhoods — but can lean more liberal on national and state matters. What many political analysts miss is that even as the suburbs have diversified, many new residents of color have adopted politics driven by the same protectionist mindset long embraced by suburban whites.

The suburbs have long and deep histories of racial exclusion, creating the lily-white neighborhoods that benefited generations of white families. After cresting in the 1950s and 1960s, however, suburban segregation receded in many regions. Beginning in the 1970s, more and more people of color settled in the suburbs in the wake of fair housing laws and court decisions, increased immigration from Asia and Latin America, and the expansion of the Black, Latino, and Asian middle class. Nationally, nonwhites made up just under 10% of suburbanites in 1970, and by 2020 they were 45%. In Los Angeles, at the cutting edge of these changes, the jump was more striking — nonwhites rose from 9% of the suburban population in 1950 to 70% in 2010.

But rather than dramatically shifting the politics of the suburbs, often these diverse suburbanites shared goals with their white neighbors — a desire for decent schools and municipal services, safety, protection of property values, and the freedom to choose where to live without discrimination. For non-white suburbanites, their arrival in suburbia was the culmination of years of civil rights struggle and a racial achievement not to be taken lightly. The right to hold property signified full inclusion.

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Thanks to a confluence of forces, the 1980s put these suburban values and politics to the test. Nowhere was this clearer than in Los Angeles.

Even as suburban diversity accelerated, industrial plants were closing and government cut services as a result of Proposition 13, which limited property taxes. At the same time, the suburbs began taking a more active role in immigrant oversight. Although authority over immigration technically resided with the federal government, during the Reagan years, federal retrenchment began shifting enforcement authority to suburbs and other localities. Suburban communities, in turn, began developing their own toolkits for controlling immigrants, drawing upon their local powers to control land use and behaviors in public spaces. 

In this altered climate, an anti-immigrant backlash erupted in the suburbs. Town after town launched actions against immigrants, particularly the undocumented. Some suburban city councils used local police powers to aid in INS/ICE crackdowns on undocumented immigrants at factories, bus stops, and apartment buildings. Many suburbs passed ordinances outlawing day laborers, pushcart vending, spontaneous games of soccer in parks, and foreign-language signage on businesses. One campaign in a Latino suburb tried to outlaw the bright paint colors on homes and businesses that some Latinos had tended to favor. These crackdowns came in wealthy suburbs and working class ones, both of which contained increasingly diverse residents.

In the suburbs of southeast Los Angeles, which had flipped from majority white to majority Latino, local officials adopted policies that especially targeted undocumented immigrants. They launched an aggressive crackdown on informal housing (like converted garages) in suburban backyards. What had once been an acceptable practice for white residents, now became essentially criminalized as such dwellings became increasingly associated with the undocumented. Suburban leaders also tended to hinder immigrant entrepreneurs, targeting them for regulatory violations instead of promoting their businesses.

Yet, racism wasn’t necessarily driving the anti-immigrant policies. The leaders behind them included both old guard whites and newly elected Latino city council members, representing the interests of middle-class homeowners. They expressed concerns about protecting property values, beautifying their suburbs, and scrambling to fill the economic void left by local plant closures. As South Gate Mayor Henry Gonzalez, who backed the paint color campaign, observed in 1998, “As people climb the ladder of success, they start thinking about property values.” Gonzalez acknowledged that some had charged “that if I were white I’d be a bigot.” But all of the complaints to him about the paint colors had been from “second- and third-generation Hispanics,” not white residents.

Local leaders worried too about the strain that dwellers of garage housing were putting on local resources, from the schools to water supplies and sewer systems. While informal housing actually met local needs for affordable housing and kept the homelessness rate low in these suburbs, at the time many residents — Latino and white alike — perceived it as a blight on the community and the crackdowns continued.

These actions brought into focus an emerging suburban politics in Los Angeles’s diversifying suburbs. Protect your property and neighborhood from encroachments that might threaten security, dampen property values, and strain local services already stretched thin. Suburbanites of all races chose to scapegoat immigrants for the struggle of local services to keep up with growth, when in truth corporate disinvestment and government cutbacks were the bigger culprits. 

In the years since, this anti-immigrant backlash spurred tremendous activism among Latinos, and helped usher in California’s blue wave, which gathered momentum by 2000 thanks in part to grassroots campaigns that linked community organizing with voter mobilization. Many California suburbanites proved to be pro-immigrant — as long as they felt that immigration was not hurting their communities. And more and more of these suburbanites were immigrants themselves. In Los Angeles, 57% of immigrants lived in suburbs by 2010 (nationwide, that number was 50%).

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Yet, today we’re seeing something of a resurgence of the suburban debates about immigration in the 1980s, spurred by common concerns about rising crime and economic pressures on families. That’s important because these suburbs in places like Encinitas in northern San Diego, Los Angeles and Orange County, and beyond, may determine which party controls the House of Representatives. Some of them are in critical swing districts. As in the 1980s, suburbanites have linked immigration to concerns that hit close to home about public safety and strains on municipal budgets posed by recent arrivals.

But this shouldn’t be surprising. It’s simply a continuation of the politics that have shaped the suburbs for more than four decades. Even as they diversified, the priorities for homeowners of all races were protection of homes, safe communities, strong schools with adequate resources, and protection of civil rights. These politics defied neat categorization as liberal or conservative. Instead, they were protectionist, and have remained so.  

For all candidates who need to run up big margins in the suburbs, understanding this complex political culture is a must. Scapegoating immigrants will only get a candidate so far, since immigrants are also suburban voters. Yet, candidates must also recognize that diverse suburbanites seek policies to shore up their communities — to promote safe, healthy neighborhoods, protect and promote homeownership, help maintain a decent standard of living, and ensure civil rights. Democratic candidates who assume liberal suburbanites are likewise liberal on immigration must understand this is not always the case when they perceive immigration as a threat to these goals.    

The suburban dream remains as strong as ever — even as the dreamers have changed. The protection of that dream may well hold the key to November’s election.

Becky Nicolaides is a research affiliate at the Huntington-USC Institute on California and the West. She is the author of The New Suburbia: How Diversity Remade Suburban Life in Los Angeles After 1945 (Oxford, 2024).

Made by History takes readers beyond the headlines with articles written and edited by professional historians. Learn more about Made by History at TIME here. Opinions expressed do not necessarily reflect the views of TIME editors.