In international politics, starting a war is often easier than ending one. History has repeatedly shown that great powers can pull the trigger with a political decision, yet the trajectory, scope, and ultimate outcome of a war rarely remain under the sole control of its initiator. The United States’ attack on Iran sits precisely at this dangerous juncture: a war of choice launched by Washington, but one whose expansion, duration, and ultimate cost will now be shaped by Tehran. This is not merely an analytical warning; it underscores one of the deepest contradictions in Donald Trump’s foreign policy. A president who rose to power promising to end “endless wars” has now placed the United States on the threshold of what could become the longest and most complex Middle Eastern conflict of a new generation.

The first key point is the distinction between a “preemptive war” and a “preventive war”—a distinction with enormous legal and strategic implications. A preemptive war occurs in response to an imminent and immediate threat; a preventive war, by contrast, is launched against a potential future threat. The U.S. strike on Iran falls into the latter category. There was no clear evidence of an immediate threat to American territory. Iran was neither on the verge of deploying a nuclear weapon nor preparing an imminent attack against vital U.S. interests.

This war was therefore not an urgent act of self-defense but a political choice—based on projections of future risk rather than response to a present danger. The problem with such wars is that their international legitimacy is fragile, and more importantly, they lack clear temporal and geographic limits.

This war was therefore not an urgent act of self-defense but a political choice—based on projections of future risk rather than response to a present danger. The problem with such wars is that their international legitimacy is fragile, and more importantly, they lack clear temporal and geographic limits.

When a country wages war to prevent “what might happen,” the definition of victory becomes ambiguous. And a war without a defined victory condition rarely has a defined end.

The Trump administration appears to be pursuing objectives that go beyond degrading Iran’s military infrastructure: regime change. Yet this is precisely the arena in which modern history has repeatedly recorded American failure. Military force can destroy facilities, eliminate commanders, and cripple infrastructure; it cannot, on its own, construct a new political order. Regime change is not the product of bombardment but of internal collapse, alternative authority, and organized political presence. Unlike many previous U.S. targets, Iran is an institutionalized state with multilayered power structures. Even a scenario involving the removal of senior leadership would not necessarily result in systemic collapse; it could instead consolidate authority in more cohesive security actors. Afghanistan, Iraq, and Libya share a common lesson: toppling a government is easier than building a stable order afterward. Washington appears, once again, to have overlooked the second phase.

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The most important analytical proposition is this: the United States started the war, but its continuation lies largely in Iran’s hands. In asymmetric conflicts, the weaker party often holds the strategic advantage of time. Iran does not need to defeat the United States militarily to prevail; it needs only to raise the costs, prolong the timeline, and widen the theater of confrontation. Tehran’s options are numerous: expanding the conflict through regional actors; exerting pressure on energy routes and the global economy; conducting limited but sustained strikes aimed at political attrition in the United States; transforming the war into a multi-front crisis that becomes increasingly difficult to control. In such a scenario, Iran’s measure of success would not be battlefield conquest but turning the war into a chronic dilemma for Washington. This mirrors the pattern the United States experienced in Iraq and Afghanistan: military superiority without political victory.

In both of his presidential campaigns, Trump pledged to extricate America from the “endless wars of the Middle East.” That message reflected deep fatigue within American society after two decades of military intervention. Yet a war with Iran stands in direct contradiction to that promise. Why? Because unlike limited operations, a confrontation with Iran has the capacity to become a protracted and chronic crisis.

Iran is a large country with regional networks and the capability to impose indirect costs. Such a war would be unlikely to end swiftly. Its domestic consequences are foreseeable: rising energy prices, market instability, deepening political divisions, and strain on European and Asian allies.

Iran is a large country with regional networks and the capability to impose indirect costs. Such a war would be unlikely to end swiftly. Its domestic consequences are foreseeable: rising energy prices, market instability, deepening political divisions, and strain on European and Asian allies.

In other words, a war intended to project American strength could divert Washington’s strategic focus away from its principal competition with China and Russia—the very strategic error U.S. planners have warned against for years.

While U.S. national security documents emphasize that the future of global competition will be shaped in the Indo-Pacific, reentering a massive military commitment in the Middle East would disperse strategic resources. Competition with China demands sustained economic, technological, and military concentration. Prolonged regional wars erode precisely that focus. Iran may not be able to defeat the United States outright, but it can keep it occupied—and in geopolitics, tying down a superpower can at times be nearly as consequential as defeating it.

Wars are usually launched under the assumption of control. Leaders believe they can calibrate escalation. Yet after the first strike, the logic of war replaces the logic of politics. Each attack invites retaliation. Each retaliation demands a new response. In this cycle, decision-makers gradually become captive to their own commitments. Withdrawal carries political costs; continuation carries strategic ones. This is how wars become “endless”—not necessarily because of the original plan, but because of the inability to exit without appearing to fail.

The U.S. strike on Iran may initially appear as a demonstration of strength, but the real danger lies in what follows. Washington has pulled the trigger, but it is no longer the sole actor shaping events. From this point forward, Tehran will influence the rhythm of the conflict—by choosing the timing, location, and intensity of its responses. This dynamic has defined many modern wars: great powers initiate them, but regional actors prolong them. If this trajectory continues, the United States may find itself trapped in the very cycle Trump once promised to end—a costly, grinding war with no clear horizon of victory. History may record this moment not as the beginning of a swift triumph, but as the point at which the United States once again entered a war far easier to begin than to leave. For ultimately, starting a war requires only one side; ending it always depends on the other—and now it is Iran that holds the decisive vote.

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