U.S. President Franklin Delano Roosevelt Credit – Bettmann Archive—Getty Images
President Donald Trump’s return to the White House has unleashed a flood of anxiety over the potential demise of what is commonly known as the post-World War II order, with its emphasis on international alliances, free trade, and respect for sovereign borders.
Yet, understanding the international world order as a creation of the post-World War II period, obscures that its roots lie earlier. Before and during World War II, President Franklin D. Roosevelt helped shepherd a system into existence which aimed to combat similar pernicious forces buffeting the world in 2025: The belief that might makes right; massive economic inequality; the adoption of restrictive trade policies that set former friends and allies against one another; and authoritarian regimes strengthening their hold on power and preying on their neighbors. It was also intended to counter the isolationism of the 1930s and Americans’ all-too-common tendency to see themselves as living in a world apart, protected by the Atlantic and Pacific oceans.
In other words, the creation of the American-led international system we live in today did not simply drop out of the sky. It came about by design—a design animated by Roosevelt’s profound belief in the links between the onset of the Great Depression and the eruption of the most destructive war in human history. This meant that winning World War II was not enough. To eradicate fascism and establish a lasting peace, the U.S. had to dedicate itself to addressing the root causes of the global economic crisis.
Given the isolationist tendencies of the U.S. public and Congress in the pre-war years—best exemplified by passage of the neutrality laws in the mid 1930s—Roosevelt’s ability to counter the economic autarky and expansionist aims of fascist Germany, Italy, and Japan was severely limited. But his first inaugural address provided unmistakable evidence that he wanted to try. In the speech, he dedicated his government to the “Good Neighbor Policy” as the guiding principle behind U.S. relations with Canada and Latin America.
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As a corollary to his efforts to promote peace abroad, Roosevelt also set out to restore the American people’s faith in democracy at home. He recognized that the misery caused by the Depression had led many Americans—like their counterparts in Europe and Asia—to question the efficacy of democratic government. The raft of programs and laws Roosevelt and Congress enacted during this era aimed to counter this disturbing tendency. They included Social Security, unemployment insurance, a massive investment in public works, and financial reforms that helped restore the credibility of America’s banking and financial sector.
While Roosevelt was promoting his New Deal, he also embraced an effort to reverse the disastrous 1930 Smoot-Hawley Tariff. Like his Secretary of State, Cordell Hull, who spearheaded trade reform, Roosevelt understood that tariffs were a tax on poor and working Americans and regarded the use of the progressive income tax as a much more equitable—and economically advantageous—means of raising revenue. He also comprehended the terrible impact the 1930 tariff, the second highest in U.S. history, had on the domestic and global economy. It increased costs at home and strangled international trade as other nations—including Great Britain, Canada, and much of Europe—retaliated.
In 1934, this effort culminated in the Reciprocal Trade Agreements Act (RTAA), which gave the executive branch the power to negotiate trade agreements. Under its terms, every bilateral agreement that was negotiated—the vast majority of which were used to lower existing tariffs—was immediately applied to every nation that enjoyed most-favored-nation status with the U.S. Hence, the objective of the RTAA was to break down economic barriers and promote freer trade. It was this process that gave birth to the multilateral rules-based freer trading system that expanded over the second half of the 20th century. Additionally, Roosevelt had a second, non-economic aim for this policy: promoting global stability and strengthening ties between democracies out of the administration’s conviction that, in the increasingly troubled world of the mid to late 1930s, the words of French economist Frederic Bastiat rang true, “If goods don’t cross borders, armies will.”
Despite Roosevelt’s best intentions, the ability of the U.S. to open the world’s markets to freer trade was hampered by the protectionist measures that many nations adopted in the wake of the Smoot-Hawley tariff. Even with Canada and Great Britain, which negotiated free trade agreements with the U.S. in 1935 and 1938 respectively, there were significant limitations. The British feared that the rise of global fascism might lead to the outbreak of war. This made it vital to prioritize trade within the British Empire to maintain strong ties, especially because British officials believed that they could not count on any help from the U.S. should war break out in Europe.
These fears were legitimate. When Adolf Hitler plunged the world into war in September 1939, it unleashed a fierce debate in the U.S. between those who argued the nation should maintain strict neutrality, and avoid any involvement in the war, and those who favored aid to the allies. By 1940, those who opposed U.S. involvement had coalesced into the powerful America First movement which gained steam and public support as the war continued to rage. Roosevelt carefully navigated around these challenges, first, through an amendment to the neutrality laws that allowed the U.S. to sell goods and war materiel to the allies on a cash and carry basis, and later, through the establishment of the Lend-Lease Act in the spring of 1941, which allowed the president to extend military aid to any nation whose defense was deemed vital to the defense of the U.S.
Isolationists vehemently opposed the creation of the Lend Lease program. But Roosevelt was able to overcome their opposition by appealing to bedrock American values; he reminded Americans that “peace cannot be bought at the cost of other people’s freedom.” He also built support for the program by tying it to the creation of a more prosperous and peaceful world after the war. He promised a future founded on four essential freedoms—freedom of speech and worship and freedom from want and fear—”everywhere in the world.”
The Japanese attack on Pearl Harbor on Dec. 7, 1941, abruptly ended the push to keep the U.S. out of the war. But Roosevelt never lost sight of the fact that isolationism might well return once the conflict was over. As such, the President expended enormous energy to foster the notion that the U.S. could not live in isolation from the rest of the world. He dismissed the unilateralism espoused by the America first movement as a failed policy. He also continued to hammer home the link between peace and prosperity.
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In 1944, this conviction drove the successful negotiations that produced the Bretton Woods Accords, which created the International Monetary Fund and World Bank. It also animated Roosevelt’s tireless efforts to establish the United Nations. Just a few weeks before he died, Roosevelt bluntly reminded Americans that the U.S. couldn’t build a peaceful world, “unless we build an economically healthy world.”
That he largely succeeded in this effort was perhaps best articulated by the preeminent historian Arthur Schlesinger Jr., who, when asked by TIME magazine to reflect on the forces that shaped the 20th century, responded with the simple observation that the world we live in wasn’t Adolf Hitler’s, Joseph Stalin’s, or Winston Churchill’s world, it was “Franklin Roosevelt’s.”
President Trump’s recent decision to launch a trade war has raised serious questions among our allies about America’s commitment to global security as Roosevelt defined it. Most economists agree that Trump’s imposition of high tariffs—which he has now largely paused for 90 days—represents a major blow to the world economy that will, as European Commissioner Ursula Von Der Leyen said, have dire consequences “for millions of people around the globe.” But Roosevelt’s crucial insight was that the costs of such trade wars aren’t just economic—they can also be political and dangerous. A trade war stands to not only weaken the Western alliance at the very moment when China is on the rise and Europe is facing its first major conflict since the end of World War II, it also comes at a time when—thanks to vast economic inequality—the efficacy of democratic government is being challenged by the similar of populist anti-democratic forces that emerged in the 1930s.
To be sure, the social and economic conditions in 2025 are not exactly the same as they were during Roosevelt’s tenure in office. The decline of high-paying manufacturing jobs in much of the Western world since the advent of the “free-market fundamentalism” in the 1990s has led to understandable calls for a more equitable global trading regime. But as we mark the 80th anniversary of Roosevelt’s sudden death on April 12, 1945, his leadership starkly highlights the costs and risks associated with the abandonment of his world.
David B. Woolner is professor of history and the Judy and Peter Blum Kovler Foundation fellow in Roosevelt studies, Marist University, senior fellow, Roosevelt Institute, and author of The Last 100 Days: FDR at War and at Peace.
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.
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