U.S.-Mexico border residents share more than a borderline. They share a common history and culture, social and economic ties, and environmental, security, energy, and public health concerns. Even so, a universally agreed upon territorial definition of the border has been elusive. There are various characterizations of the spatial dimensions of the border, depending on the issue at hand, and policymakers and scholars often avoid this prickly question altogether by simply talking about “the border” without defining the area it includes. This policy brief outlines different territorial descriptions of the U.S.-Mexico border across federal entities, formal binational agreements, and political-administrative units; explores the complexity of defining the border region; and points out the disadvantages of its overlapping and conflicting definitions—and the necessity of defining its territorial lines to develop and implement effective public policies that address the region’s issues.
The Boundary, the Border Region, and Public Policy
The boundary line between Mexico and the U.S. stretches 1,951 miles. It was largely set in the mid-19th century by the 1848 Treaty of Guadalupe Hidalgo and the 1853 Gadsden Purchase. Although there were small land disputes, they were minor and fully resolved by the 1960s. The boundary, however, is not the border. There is in fact no clear consensus on what truly constitutes the border region.1 Unlike the U.S.-Mexico boundary line, “the border region” has a more convoluted meaning, one that follows intricate but not coterminous political, administrative, economic, cultural, and social interests and views.
Not having a standard territorial definition of the U.S.-Mexico border region has consequences for public policy. Treaties usually define the border region by miles/kilometers on either side of the international boundaries, covering only small portions of some counties and severing the defined political-administrative units (i.e., counties and municipios) of both countries. This makes it difficult to advocate for programs and resources or analyze the populations who are truly in need of services; impedes local political organization; incentivizes local governments and federal agencies to manipulate the definition based on organizational rather than regional interests; and makes cooperation and joint territorial management difficult. Setting an agreed territorial definition of the border would solve most of these issues. A broader debate about what encompasses the border region would improve research, data analysis, and public policy implementation to help depoliticize border management and serve the development of the region.
Varying Definitions of the Border: The Local Perspective
Figure 1 — Counties and Municipios on the U.S.-Mexico Border Region Showing Three Different Definitions of the Borderlands
Figure 1 illustrates the primary approach most academics, political actors, policymakers, and the media employ to talk about the U.S.-Mexico border region. The area is roughly composed of local political-administrative units that directly touch the official boundary line, and includes 23 U.S. counties and 36 Mexican municipios2 (both are shown in teal).
This definition is arbitrary, however, given that border issues are not limited to those that concern local political-administrative units adjacent to the borderline. For this reason, border counties and municipios that do not directly touch the boundary are often included by others as part of the border region depending on the issue at hand, such as shared natural resources, sociocultural ties, economic interactions, legal and illegal crossborder flows, as well as demographic similarities (such counties and municipios are shown in orange).
Defining the U.S.-Mexico border region by local political-administrative units is analytically useful, as most statistical data are collected at that level, and local governments can articulate the border’s interests to aid in the analysis, creation, and implementation of public policy. But it would further help if there were a consensus on the definition—which does not exist even among academics.3 The U.S.-Mex Political Analysis Tool (US-Mex PAT) project of Arizona State University, for example, defines the border as 37 U.S. counties and 78 Mexican municipios,4 which clearly differs from alternative definitions among academics.5 As Anderson and Gerber put it:
This focus does not resolve a number of additional problems, however, as it still remains to determine how “deep” the border is. That is, how far into the United States and Mexico do border influences extend? This is an area of investigation for future research. Given the state of border studies, any definition we might offer now would be somewhat arbitrary.6
Varying Definitions of the Border: The State Perspective
Statewide political motivations also interfere with a broad consensus on a territorial definition of the border region. Through Senate Bill 501 in 1999, for example, the Legislature of the state of Texas, which covers the longest stretch of the U.S.-Mexico border, added several counties (depicted in yellow in Figure 1) to the border region—including Bexar County, which contains the San Antonio metropolitan area. This definition had also previously been used by the then-Texas Comptroller of Public Accounts, John Sharp.7 The Legislature cited the growing population of the Texas-Mexico border and the number of residents of the region who lack access to state agency resources and services as reasons for the expanded definition.8 S.B. 501 brought the number of Texas counties considered part of the border region to 43, and linked them directly to state public policies for the border region.
Another definition includes all of the states adjacent to the borderline. This definition encompasses 10 states—four in the U.S. and six in Mexico—with a combined population of 100 million people.9 This definition allows a broader understanding of the concerns, issues, and opportunities regarding the border shared by state authorities (e.g., trade, environmental resources, labor markets, infrastructure, etc.), but it—absurdly—includes places like Northern California and the Texas Panhandle as part of the border, which is difficult to justify.
This state-based definition of the border region is used by the Border Governors Conference (BGC), established in 1980.10 A border governors’ meeting is held periodically, although political considerations and partisan disagreements often get in the way—the 2010 BGC was derailed by Arizona’s controversial S.B. 107011 and the conference has not met since 2012. The BGC produces joint declarations but has little power to force issues onto the national policy agenda.12 A similar group, the Border Legislative Conference (BLC), is composed of federal and state legislators who represent regional districts, but legislators participate on a voluntary basis. Moreover, it appears to have no influence on agenda setting for the border.13 Both groups are constrained by the supremacy of the federal agenda over that of state and local officials.
Clearly, the BGC and the BLC discuss economic development, tourism and travel, agriculture and livestock, science and technology, energy, environment, water, wildlife, customs and logistics, border crossings, migration, security, education, public health, and emergency management, but with minimal impact on the border policy agenda as set in the national capitals. Furthermore, their border definition often considers state interests in areas such as taxation, public services, public/private partnerships, trade, and law enforcement, areas in which the states sometimes compete with one another.
Varying Definitions of the Border: The National Perspective
The third and most fragmented territorial definition of the U.S.-Mexico border region comes from the federal government. The most common definition of the border by the U.S. and Mexican governments is found in the “1983 Agreement between the United States of America and the United Mexican States on Cooperation for the Protection and Improvement of the Environment on the Border Area,” also known as La Paz Agreement. U.S. President Ronald Reagan and Mexican President Miguel de la Madrid Hurtado signed the agreement in response to environmental problems in the U.S.-Mexico border region. Article 4 defines the “border area” as the 100 kilometers (62 miles) on either side of the inland and maritime boundaries between the United States and Mexico. This definition includes the border cities and towns along the boundary where pollution and other environmental problems could spill to the other side. Even so, the definition does not cover the full geographical extent of crossborder watersheds and sub-watersheds.14
Complicating this definition of the border, the La Paz Agreement area includes in whole or in part 44 counties and 80 municipios,15 because the definition refers to a linear measure (kilometers/miles), that does not conform to the boundaries of political-administrative bodies (counties and municipios). Two institutions—the Border Environment Cooperation Commission (BECC) and the North American Development Bank (NADB), created in 1993 through the North American Free Trade Agreement (NAFTA)—first operated with the same 100-kilometer border definition, but in 2004 the U.S. Congress passed legislation redefining the border region, and the charter was amended to define the border region as 100 kilometers north of the boundary in the United States and 300 kilometers south into Mexico.16 The Pan-American Organization, a binational international agency focused on health, also has its own definition of the border, which it says consists of 48 U.S. counties and 94 municipios.17
Figure 2 — Territorial Definition of the Border for U.S. Federal Law Enforcement Purposes
In law enforcement and policing, the definition of the border encompasses an even broader geographical area. According to 8 U.S. Code §1357, which outlines immigration enforcement, U.S. agencies can refer to a “reasonable distance from any external boundary of the United States” and any officer or employee of the service designated by the attorney general may—without a warrant—board and search any vessel, railway car, aircraft, conveyance, vehicle for the “purpose of patrolling the border to prevent the illegal entry of aliens into the United States.”18 “Reasonable distance” was later defined as 100 air miles from any external boundary of the United States. Customs and Border Protection agents can thus set up immigration checkpoints in a much larger geographical area than almost any other U.S. agency.19 It is not clear why 100 air miles was chosen and why the populations that live within that zone were not consulted, but nearly two-thirds of the U.S. population falls within that definition of the border (Figure 2).20
Mexico has an even more complex definition of the border region for the customs and law enforcement purposes. It designates an area of 20 kilometers (12.42 miles) from Mexico’s side of the boundary as the border; at other times, entire municipios are listed as part of the border region, with no specific justification.21 Border towns and cities, however, are border “free zones,” and U.S. citizens and residents may travel there without obtaining a visitor’s permit (Forma Migratoria Multiple-FMM),22 and Mexican citizens may bring in via land crossing $300-500 worth of merchandise with only a system of random checks for tax collection purposes.23
Overlapping and Conflicting Definitions
Clearly, there are overlapping and conflicting territorial definitions of the U.S.-Mexico border region. A map of how the southwest border region overlaps under the different definitions is seen in Figure 3. There are, of course, arguments for having different definitions of the border. For academics, for example, a consistent operationalization may be difficult as it depends on what they are researching and how.24 Another argument is that public policy issues do not necessarily coincide with a single territorial definition and forcing a single definition based on territorial demarcations might complicate the work of different agencies. What’s more, border watersheds may stretch well beyond a territorial definition useful to law enforcement, trade, or environmental issues. However, border issues have become increasingly complex. A standard understanding of the border’s parameters is necessary to create the binational institutions that eventually evolve into effective joint territorial managers of these issues. As previously mentioned, border leaders are partly unable to advocate for the region’s interest because no one knows what the border region really encompasses.
Figure 3 — Overlapping Territorial Definitions of the U.S.-Mexico Border
Why Is It Important to Agree?
The political environment in the U.S. today dictates the continued construction of a border wall, that human mobility be restricted at the border, and joint natural resource and environmental management take a back seat to national infrastructure and economic development. However, this border management model is not sustainable. The border region is, by definition, a place of interactions—economic, social, and cultural—with people, goods, capital, and services continually flowing back and forth across the border. Additionally, the region is growing and current territorial definitions complicate the management of population growth, climate change and other environmental challenges, as well as crossborder activities, legal and illegal.25 The myriad definitions are insufficient to effectively manage the border region’s policy issues, which affect local, state, national, and international interests.
Unilateral approaches to managing the U.S.-Mexico border region are questionable because segregating markets by separating crossborder communities, rather than taking advantage of their joint potential, impoverishes populations and sets back economic development. The region is a dynamic territory, with borderlanders using resources to maximize individual and household wealth—working, shopping, investing, and carrying out activities in areas they believe their resources will be more efficiently allocated. Impeding these calculations will force people to spend more resources than required on a particular good and consequently lead to a loss of individual and collective wealth—and also damage the cultural and social ties that support healthy communities and facilitate the larger political and diplomatic work needed to build effective governance institutions on both sides of the border.
Effective regional management requires close political coordination among all three levels of government—local, state, and national—within each country and across the boundary line. This is a multi-layered, complex political landscape that calls for an overarching set of institutions. For instance, a border commission, backed by federal and political will, with working groups could coordinate the multiple agencies that govern the border space and articulate the needs of local communities to provide legitimacy to a joint administrative system.
Thus, a binational, agreed-upon territorial definition of the border region would facilitate governance and support the well-being of border residents. Although this model appears counter to the concept of sovereignty, a border commission to coordinate the work of all agencies involved in border management could reinforce sovereignty while bringing order and coordination to a region whose many agencies appear to be operating independently and without regard to the activities of others.
Current territorial demarcations of the U.S.-Mexico border region do not facilitate the creation of institutions that provide good governance; do not leverage the border as a resource26 for binational prosperity; and do not represent the interests of borderlanders. Instead, they are often sets of arbitrary, and at times unilateral, definitions of what is fundamentally a shared space. Management of the region should be shared at a basic level. Fragmented territorial definitions impose excessive costs on borderlanders, who have to spend increasing amounts of money, time, and energy if they want to interact with each other across borderlines, and who find it increasingly difficult to take advantage of goods and services offered on the other side at better prices. The 21st century U.S.-Mexico border requires a territorial reorganization and a common definition to create effective governance mechanisms for a competitive and sustainable region.
1. Paul Ganster, ed., The U.S.-Mexican Border Environment: A Road Map to a Sustainable 2020 (San Diego State University Press, 2000).
2. A municipio is the Mexican political-administrative unit equivalent to a U.S. county.
3. Gerber, Lara-Valencia, and de la Parra include 40 municipios and 24 counties adjacent to the boundary. See James Gerber, Francisco Lara-Valencia, and Carlos de la Parra, “Re-Imagining the U.S.-Mexico Border: Policies Toward a More Competitive and Sustainable Transborder Region,” Global Economy Journal 10, no. 2 (2010). Mora and Dávila confine the border to 23 counties and 35 municipios, which they also say are “adjacent” to the boundary line. See Marie T. Mora and Alberto Dávila, Labor market issues along the US–Mexico border (Tucson: University of Arizona Press, 2009). Anderson and Gerber include 25 counties and 38 municipios, which they argue touch the borderline. See Joan B. Anderson and James Gerber, Fifty Years of Change on the U.S-Mexico Border: Growth, Development, and Quality of Life (Austin, Texas: University of Texas Press, 2008). De Cosío and Boadella argue that “Perhaps there is one legal border definition, which is the ‘imaginary line’ that divides Mexico and the United States … [but] … There are many operational definitions of the border. Each definition responds to the specific needs of the defining organization. Any consensus is unlikely as to what is meant by the border region … In addition, for some observers, the border should also include other metropolitan areas that are far beyond the boundary because either they are influenced by the border, or they influence the border. San Antonio, Texas, and Monterrey, Nuevo León, are classic examples since these two cities consider themselves the gateway to the United States or to Mexico” (pp. 2-3). See Federico Gerardo De Cosío and Andrés Boadella, “Demographic Factors Affecting the U.S.- Mexico Border Health Status,” in Life, Death, and In-between on the U.S.-Mexico Border: Así Es la Vida, eds. Martha Oehmke Loustaunau and Mary Sánchez-Bane (Westport, CT: Bergin & Garvey, 1999).
4. See U.S.-Mexico Political Analysis Tool at http://usmexpat.com/wp-content/uploads/2014/04/Volume-I.pdf.
5. See endnote 3.
6. See Joan B. Anderson and James Gerber, Fifty Years of Change on the U.S-Mexico Border: Growth, Development, and Quality of Life. (Austin, Texas: University of Texas Press, 2008): 11.
7. John Sharp, “Bordering the Future” (Office of the Comptroller of Public Accounts: Austin, Texas, 1998).
8. Texas Legislature, S.B. 501, 76th Regular Session, 1999, http://www.lrl.state.tx.us/legis/BillSearch/BillDetails.cfm?legSession=76-0&billtypeDetail=SB&billNumberDetail=501&billSuffixDetail=&startRow=1&IDlist= &unClicklist=&number=100.
9. U.S. Department of State, Bureau of Western Hemisphere Affairs, Factsheet. See http://www.state.gov/r/pa/ei/bgn/35749.htm.
10. See Arizona Office of Tourism at https://tourism.az.gov/border-governors-conference.
11. Senate Bill 1070, formally titled the “Support Our Law Enforcement and Safe Neighborhoods Act,” was an anti-immigration bill signed by former Arizona Gov. Jan Brewer on April 23, 2010. The law “compelled police to ask for papers and allowed officers to arrest a person without a warrant if the officer believed the person has committed an offense that makes them deportable. The law also made it a crime to fail to carry registration papers and for people in the country illegally to solicit work.” See Nigel Duara, “Arizona’s once-feared immigration law, SB 1070, loses most of its power in settlement,” Los Angeles Times, September 15, 2016, http://www.latimes.com/nation/la-na-arizona-law-20160915-snap-story.html.
12. See the Texas Department of State at https://www.sos.state.tx.us/border/bmaconf.shtml.
13. See the Border Legislators Conference at http://www.borderlegislators.org/home_eng.htm.
14. Paul Ganster, “Evolving Environmental Management and Community Engagement at the U.S.-Mexican Border,” Eurasia Border Review 5, no. 1 (Spring 2014):19-39.
15. United States-Mexico Border Health Commission, http://www.borderhealth.org/border_region.php.
16. Public Law No: 108-215. See https://www.congress.gov/108/plaws/publ215/PLAW-108publ215.pdf. Agreement Between the Government of the United States of America and the Government of the United Mexican States Concerning the Establishment of a Border Environment Cooperation Commission and a North American Development Bank, Chapter V, Article II, p. 26. See http://www.nadb.org/pdfs/publications/Charter_2004_Eng.pdf.
17. Pan-American Health Organization. See http://www.paho.org/salud-en-las-americas-2012./index.php?option=com_docman&task=doc_view&gid=153&Itemid.
18. 8 U.S. Code §1357–Powers of immigration officers and employees, 2011 Edition. See https://www.gpo.gov/fdsys/pkg/USCODE-2011-title8/html/USCODE-2011-title8-chap12-subchapII-partIX-sec1357.htm.
19. Code of Federal Regulations, Title 8–Aliens and Nationality, https://www.gpo.gov/fdsys/pkg/CFR-2001-title8-vol1/xml/CFR-2001-title8-vol1-sec287-1.xml.
20. American Civil Liberties Union, “Fact Sheet on Customs and Border Protection’s 100-mile Zone,” https://www.aclu.org/other/aclu-factsheet-customs-and-border-protections-100-mile-zone?redirect=immigrants-rights/aclu-fact-sheet-customs-and-border-protections-100-mile-zone.
21. See http://www.sat.gob.mx/aduanas/pasajeros/Paginas/Franja_region_fronteriza.aspx.
22. See U.S Department of State, Bureau of Consular Affairs. See https://travel.state.gov/content/passports/en/country/mexico.html.
23. Servicio de Administración Tributaria (SAT), Secretaría de Hacienda y Crédito Público de México. See http://www.sat.gob.mx/BienvenidoaMexico/Paginas/mercancia_puedes_ingresar.html.
24. See James Gerber, “Human and Physical Infrastructure Along the U.S. Border with Mexico,” 2009, at http://www.bakerinstitute.org/research/human-and-physical-infrastructure-along-the-us-border-with-mexico, page 32.
25. Kathy Staudt and Irasema Coronado, Fronteras No Más: Toward Social Justice at the U.S.-Mexico Border (Palgrave Macmillan, 2003): 10-15.
26. Christophe Sohn, “The Border as a Resources in the Global Urban Space: A Contribution to the Crossborder Metropolis Hypothesis,” International Journal of Urban and Regional Research 38, no. 5 (2013): 1697-1711.
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