The U.S. decision to actively participate in the Israeli strike on Iran and bomb the Fordow nuclear facility presents an opportunity to examine, from a historical perspective, the long-standing conflict within American leadership between two worldviews: one rooted in isolationism and the other advocating for a proactive superpower role.
America’s geographic location – across the Atlantic Ocean—has always served as reinforcement for its isolationist stance, favoring internal American interests over entanglements in distant conflicts. In his farewell address, George Washington, the first U.S. president, urged America to leverage its geographic detachment and avoid involvement in European affairs, which he argued were irrelevant to American interests.
This isolationist outlook was formally codified in U.S. foreign policy in 1823 by President James Monroe. This policy, later known as the “Monroe Doctrine,” established that the U.S. would refrain from involvement in European wars and would not tolerate European colonialism in the Americas. In contrast to this approach, many voices within the American leadership advocated for a firm stance and involvement in global conflicts, especially those that might threaten American interests.
This gap between worldviews remains evident today, particularly in the intra-Republican struggle between the MAGA/“America First” school, which opposes foreign entanglements, and the hawkish faction that supports active global engagement.
In the following sections, I will review some of the global wars, conflicts, and events of the past century in which the U.S. intervened, as well as the varying approaches of its leaders. In my view, while in many cases it was a seemingly random event that dragged the U.S. into war, in the final analysis, the United States cannot avoid—and in most cases does not wish to avoid—its historical role as leader of the free world and shaper of the global order.
World War I: The Telegram Effect
On January 16, 1917, a coded telegram sent by German Foreign Minister Arthur Zimmermann reached the desk of Germany’s ambassador to the United States, Count Johann Heinrich von Bernstorff. Von Bernstorff was instructed by his foreign minister to forward a secret message to the German ambassador in Mexico, Heinrich von Eckardt. In the telegram, von Eckardt was authorized to offer the Mexican government an alliance with Germany against the United States. In return, Germany would provide economic and diplomatic support for a Mexican effort to reclaim the territories of Texas, New Mexico, and Arizona—regions that were once under Mexican sovereignty.
The telegram and Germany’s attempt to interfere in U.S.–Mexico relations were part of a broader German strategy to break the deadlock on the Western Front in its war against France and Britain. Germany launched a campaign of unrestricted submarine warfare, targeting even neutral vessels, to block supplies to the British and force them into surrender.
The Germans feared this escalation might provoke American intervention in the war, and to distract the U.S., they tried to entangle it in a separate war of its own. However, in attempting to ignite such a conflict—using the Zimmermann Telegram—they failed to consider that Britain had cut Germany’s direct communication cables with the U.S., allowing British intelligence to intercept transatlantic messages via alternative routes. British intelligence intercepted the telegram and passed it to the Americans. This move proved to be the final straw: shortly thereafter, the U.S. severed diplomatic ties with Germany.
Although President Woodrow Wilson was reelected in 1916 on the slogan “He kept us out of war,” the Zimmermann Telegram forced him to reverse course. On April 2, 1917—roughly two and a half months after the telegram’s interception—Wilson asked Congress to declare war on Germany. America’s entry into the war undoubtedly changed the course of history, and the Zimmermann Telegram played a critical role in this shift. Still, this event did not occur in a vacuum, as American public sentiment had already been increasingly anti-German.
Between the World Wars: A Return to Isolationism
America’s ambivalence toward global involvement, and particularly toward Europe, persisted after World War I. On the one hand, President Wilson championed the creation of the League of Nations—an international body formed after the 1920 Paris Peace Conference (and later replaced by the United Nations)—to prevent war and resolve disputes through diplomacy. On the other hand, the U.S. Senate refused to ratify American membership in the organization, fearing the loss of national sovereignty and potential entanglement in future conflicts.
A few years later, in October 1929, following a prolonged period during which U.S. banks had issued large, unsecured loans, the stock market crashed on Wall Street, marking the beginning of the Great Depression. Unemployment soared to unprecedented levels, businesses shut down, and many banks collapsed. To respond to the crisis, President Herbert Hoover introduced a series of measures, including the Smoot–Hawley Tariff Act, which raised import duties. This move triggered a global wave of protectionism, bearing similarities to the tariff hikes imposed by President Donald Trump decades later.
These events quickly spread throughout Europe, particularly in Germany. The German economy began to collapse, and by January 1933, one in three Germans was unemployed. The resulting economic despair created fertile ground for the rise to power of Adolf Hitler and the Nazi Party.
President Franklin Delano Roosevelt, who replaced Hoover, implemented the “New Deal”—a policy aimed at economic recovery and reform to lift the U.S. out of the Depression. Despite his preference for a more assertive foreign policy, Roosevelt’s administration remained committed to isolationism to secure congressional backing for his domestic agenda.
Given this reality, it is no surprise that in the 1920s and 1930s, the American political climate did not permit involvement in global affairs. The dominant approach remained isolationist, focused on domestic issues and the protection of economic interests.
World War II: A Response to an Existential Threat
At the outbreak of World War II, the United States, adhering to its isolationist approach, adopted an official position of neutrality and refrained from participating in the conflict as an active combatant. During the war’s first year, Congress allowed other nations to purchase American military supplies only on a “cash and carry” basis. President Roosevelt, following the advice of his military advisors, believed that Britain would be defeated and that America’s role should focus on defending the Western Hemisphere.
This position began to shift gradually in 1941, until which point the British, French, and other Allies stood alone on the front lines against the Axis powers. In late January of that year, Republican presidential candidate Wendell Willkie visited Britain and met with Winston Churchill. Willkie, who supported increased American involvement in the war, carried a letter from President Roosevelt conveying support for Britain. Churchill’s subsequent address to the British people concluded with the famous lines: “We shall not fail or falter; we shall not weaken or tire… Give us the tools, and we will finish the job.”
Churchill’s appeal to America was not brushed aside. On March 11, 1941, Congress passed the Lend-Lease Act, which allowed the U.S. president to supply equipment and food to other countries for the promotion of American interests. Later that year, the act became the basis for escalating American assistance—initially to Britain alone, and later to the Soviet Union, which received thousands of tanks, trucks, and aircraft from the United States.
Until late 1941, the U.S. managed to stay out of the war, maintaining a position that partially aligned with the Monroe Doctrine, though it provided support to the Allies. On the morning of Sunday, December 7, Japan launched a surprise attack on the American base in the Pacific—Pearl Harbor. The attack, which claimed the lives of nearly 2,500 Americans, was followed within hours by Japan’s declaration of war on the United States. The next day, Roosevelt delivered his “Day of Infamy” speech, declaring war on the Japanese Empire.
While America’s entry into World War II is widely remembered as a direct consequence of the attack on Pearl Harbor, as shown above, U.S. involvement had begun gradually nearly a year earlier. The trauma and shame felt by Americans in the wake of the attack made continued passivity impossible.
U.S. involvement in the war—from its beginning at Pearl Harbor to its conclusion with the defeat of Japan via the atomic bombings of Hiroshima and Nagasaki, and the collapse of the Nazi regime in Europe and other fronts—profoundly reshaped history. In retrospect, it is difficult to say whether the United States would have entered the war without that December 1941 attack. However, it is reasonable to assume that the outcome would have been dramatically different had the U.S. chosen to adhere to isolationism.
The Cold War: An Era of Constant Intervention
Following World War II, Britain and France were preoccupied with rebuilding from the devastation, and a new bipolar global order emerged, led by two superpowers: the United States and the Soviet Union. During the war, the collaboration between these two powers against the common Nazi enemy had somewhat muted their ideological differences between Soviet communism and Western capitalism. However, with the fall of the Third Reich, the roots of their conflict resurfaced, fueled not only by ideological rifts but also by territorial disputes over the spoils of Nazi-controlled regions.
The two sides attempted to divide spheres of influence in Europe at the Yalta Conference and later at the Potsdam Conference, held at the end of the war. Despite the formal agreements, the Soviet Union’s desire to expand its influence and impose communism worldwide clashed with American fears of such a scenario and the potential erosion of democratic and capitalist principles. These fears led the U.S. to abandon its isolationist policy during this period.
This was the backdrop for the outbreak of the Cold War between the blocs, which would only come to an end with the collapse of the Soviet Union and the fall of the Berlin Wall in the early 1990s. During the Cold War years, the U.S. adopted the “domino theory,” which posited that the fall of one country to communism would lead to the collapse of its neighbors. The theory, initially formulated by President Harry Truman, was later officially declared by President Dwight D. Eisenhower regarding the situations in India and China.
The ideological battles between the blocs began escalating into military conflicts during the 1950s. However, they never evolved into a global war, mainly due to the balance of terror that developed once the Soviet Union acquired nuclear weapons in 1949. Nonetheless, the United States adopted a clear stance aimed at preventing the spread of communism, whether through direct military intervention or by supporting proxy forces.
American involvement in the confrontation with the Soviet bloc reached its peak in three key events. The first was the Korean War. In the 1950s, the U.S. deployed its military to Korea to halt the invasion of the South by the Soviet-backed North Koreans. American forces succeeded in capturing the northern capital but were later pushed back by the Chinese army. The armistice line that divided North and South Korea became one of the primary borders between the communist bloc and the West.
Next came the Cuban Missile Crisis. In the early 1960s, it was revealed that the Soviets were constructing a missile base on the Caribbean island of Cuba. In response, the U.S. imposed a blockade on Cuba and demanded the dismantling of the base. The crisis ended with an agreement between U.S. President John F. Kennedy and Soviet Premier Nikita Khrushchev, but came dangerously close to igniting direct war between the two nuclear superpowers.
The third event was the Vietnam War, which began with American and Soviet involvement in the civil war between the communist-influenced North and the anti-communist South. From 1965, the U.S. became entangled in a direct war with North Vietnam, which ended only a decade later in American defeat and the unification of the country under communist rule. This defeat left a particularly traumatic mark on the American national consciousness and would later shape the country’s attitude toward future conflicts in distant regions. Alongside fears of entanglement in a nuclear war—underscored by the Cuban Missile Crisis—these events significantly bolstered the appeal of the isolationist approach.
From Iraq to Afghanistan: Establishing a Foothold in the Middle East
The collapse of the Soviet bloc and the end of the Cold War in the early 1990s left the United States as the world’s sole superpower—a fact that once again forced it to abandon isolationist positions and adapt to a new global environment that it now led, often through international coalitions it assembled. In this new reality, the U.S. began intervening in conflicts around the world, particularly in the Middle East and Asia. The first such example was the First Gulf War: in 1990–1991, the U.S. justified its leadership of the international coalition that fought Iraq and liberated Kuwait from Saddam Hussein’s invasion by citing a violation of international law, the threat to global oil supply stability, and the need to protect strategic and economic interests.
The Second Gulf War (the Iraq War), from 2003 to 2011, was a continuation of the first, but this time aimed to topple Saddam Hussein’s regime, which was deemed a threat to world peace and accused of possessing weapons of mass destruction. After deposing the regime, the U.S. and its coalition partners continued to battle local guerrilla forces in Iraq—a campaign that marked a clear departure from the American isolationist approach.
At the same time, the U.S. assumed a central role in the global war on terror—a campaign with international dimensions, declared by President George W. Bush after the September 11 attacks. These attacks dramatically transformed America’s national security outlook and prompted a pursuit of terrorist organizations and regimes throughout the Middle East, particularly al-Qaeda and its leader, Osama bin Laden. Subsequently, the U.S. invaded Afghanistan to topple the Taliban regime, which had hosted al-Qaeda, the group responsible for the attacks that shocked America. The declared aim of the war was to destroy the terror infrastructure and prevent future terrorist operations.
The Strike on Iran: A Clear Message to the World
For many years, successive U.S. presidents declared that Iran would not be allowed to obtain nuclear weapons. This declaration was only partially enforced, mainly through diplomatic means and economic sanctions against the Ayatollah regime. But only after Israel’s direct attack on Iran and its nuclear infrastructure in June of this year was the U.S. compelled to cross the Rubicon and make a decisive—perhaps unprecedented—move in recent decades: to join an ally’s military campaign against a hostile state. Through its participation in the strike on the Fordow nuclear facility, the U.S. sent a clear message to the world: we prefer diplomatic solutions or agreements, but we will not hesitate to use military force when an American or global interest is under significant threat.
Ultimately, the history of America’s involvement in regional and global wars swings between two poles: the isolationist approach, which prefers to deal only with internal American interests, and the superpower approach, which seeks to shape the global order and does not shy away from intervening in regional conflicts—even ones far removed from American soil.
Over the years, American interventions have been based on considerations perceived to serve U.S. interests, as well as concerns for global stability, both economic and ideological. Yet the U.S. has often been drawn into conflicts in which it initially avoided involvement, only to be compelled by major events (the Iraqi invasion of Kuwait, the 9/11 attacks, the Zimmermann Telegram).
An examination of the sequence of regional and global conflicts in which the U.S. ultimately intervened compels the conclusion that even when there was a specific trigger for intervention, it reflected a broader superpower doctrine—one that seeks to define the rules of the global game and, ultimately, prevails over isolationist forces. Or in the words of Winston Churchill: “History is always shaped by something—if not by a certain doubt, then by a telegram received.”
