One of the more interesting illustrations of liberalism comes from the foreign policy of the United States during the early twentieth century. During this period, the United States was liberal, but according to the dominant historical narrative, also imperialistic (see Meiser 2015). So, there appears to be a contradiction. If we take a closer look we see that the United States was more restrained than commonly believed, particularly relative to other great powers of that era. One simple measure is the level of colonial territory it accrued compared to other great powers. By 1913, the United States claimed 310,000 square kilometres of colonial territory, compared to 2,360,000 for Belgium, 2,940,000 for Germany and 32,860,000 for the United Kingdom (Bairoch 1993, 83). In fact, the bulk of American colonial holdings was due to the annexation of the Philippines and Puerto Rico, which it inherited after defeating Spain in the Spanish-American War of 1898. The United States exhibited such restraint because, as suggested by liberal theory, its political structure limited expansionism. Examining US–Mexico relations during the early twentieth century helps illustrate the causes of this American restraint.
In the spring of 1914, the United States invaded the Mexican city of Veracruz because of a dispute over the detention of several American sailors in Mexico. However, US–Mexican relations were already troubled because of President Woodrow Wilson’s liberal belief that it was the duty of the United States to bring democracy to Mexico, which was a dictatorship. The initial objectives of the American war plan were to occupy Veracruz and neighbouring Tampico and then blockade the east coast of Mexico until American honour was vindicated – or a regime change occurred in Mexico. After American forces landed in Veracruz, senior military leaders and Wilson’s top diplomatic advisor in Mexico advocated an escalation of the political objectives to include occupation of Mexico City – there were also vocal proponents who advocated the full occupation of Mexico. Wilson did not actually follow any of the advice he received. Instead, he reduced his war aims, halted his forces at Veracruz and withdrew US forces within a few months. Wilson exercised restraint because of American public opposition, his own personal values, unified Mexican hostility and the military losses incurred in the fighting. International opinion also appears to have influenced Wilson’s thinking as anti-Americanism began to sweep through Latin America. As Arthur Link points out, ‘Altogether, it was an unhappy time for a President and a people who claimed the moral leadership of the world’ (Link 1956, 405).
By 1919, a pro-interventionist coalition developed in the United States built on frustration with President Wilson’s prior restraint and new fears over the Mexican Constitution of 1917, which gave the Mexican people ownership of all subsoil resources. This potentially endangered foreign ownership of mines and oilfields in Mexico. Interventionists wanted to turn Mexico into an American protectorate – or at least seize the Mexican oil fields. This coalition moved the country toward intervention while Wilson was distracted by peace negotiations in Europe and then bedridden by a stroke. The path to intervention was blocked only after Wilson recovered sufficiently to regain command of the policy agenda and sever the ties between the interventionists. Wilson had two main reasons for avoiding the more belligerent policy path. First, he saw the Houses of Congress (with the support of some members of the executive branch) attempting to determine the foreign policy of the United States, which Wilson viewed as unconstitutional. In the American system, the president has the authority to conduct foreign policy. His assertion of authority over foreign policy with Mexico was therefore a clear attempt to check the power of Congress in policymaking. Second, Wilson was determined to maintain a policy consistent with the norm of anti-imperialism, but also the norm of self-determination – the process by which a country determines its own statehood and chooses its own form of government. Both of these norms remain bedrocks of liberal theory today.
US relations with Mexico in this case show how institutional and normative domestic structures restrained the use of violent power. These institutional restraints can break down if the political culture of a society does not include a strong dose of liberal norms. For example, anti-statism (a belief that the power of the government should be limited) and anti-imperialism (a belief that conquest of foreign peoples is wrong) are liberal norms. A society infused by liberal norms has an added level of restraint above and beyond the purely institutional limitations on state power. A liberal citizenry will naturally oppose government actions that threaten individual liberty and choose representatives that will act on liberal preferences. The institutional separation of powers in the United States allowed Wilson to block the interventionist efforts of Congress and others. The liberal norm of anti-imperialism restrained American expansion through the mechanisms of public opinion and the personal values of the president of the United States. Institutions and norms worked symbiotically. International opinion put additional pressure on American political leaders due to increasing trade opportunities with Latin American countries throughout the early 1900s. Precisely as liberal theory details, the absolute gains and opportunities offered by trade, together with preferences for self-determination and non-interference, acted as a restraint on US expansionism toward Mexico in this most imperial of periods in world history.