In a recent article, I warned that tensions between the world’s major powers are heating up in ways that could set the stage for a global war. This time I want to dig deeper into one of the most likely flashpoints: Iran. I first want to consider if the US will Commit Ground Troops in a War on Iran: A U.S. ground invasion of Iran is improbable as an opening move, but not impossible if the conflict escalates. History shows Washington has always hesitated to put troops directly into Iran. The geography explains why: Iran is a fortress surrounded by mountains, with deserts and salt flats in its interior, and a population of more than 85 million that can be mobilised in defence. Saddam Hussein’s failure to break through the Zagros in eight years of war is a reminder of how inhospitable the terrain is to an invader. U.S. generals know this would not be Iraq 2003, where armoured columns swept to Baghdad in weeks; a march on Tehran could stall in mountain passes and dense urban centres, turning quickly into a quagmire. From a game theory perspective, this caution makes sense. The United States gains little from committing ground troops unless forced by events. The costs—casualties, political backlash, and the risk of getting trapped—are high, while the payoff is uncertain. The rational equilibrium has long been limited confrontation: airstrikes, sanctions, covert operations, and proxy wars. Iran, by contrast, knows it can't win conventionally and instead seeks to shape the game. Its best strategy is to lure America into exactly the fight it wants to avoid: a protracted ground war that unites Iranians, stretches U.S. supply lines, and erodes U.S. domestic resolve. By calibrating provocations—such as strikes on U.S. bases, harassment in the Strait of Hormuz, or attacks via proxies—Iran can raise pressure on Washington to respond more forcefully. America’s global reputation creates a trap: if it fails to retaliate, credibility suffers; if it escalates too far, it risks the quagmire Tehran has prepared for. Israel’s role complicates this further. While publicly aligned with America, their deeper strategic interests are not identical. Israel wants Iran neutralised, but also benefits if the U.S. exhausts itself in the process, potentially leaving Israel as the dominant regional military power. Entangling America in a long war with Iran serves both goals: weakening its greatest rival and draining its patron. If the US entered a Ground War in Iran, could they win Quickly? If U.S. ground troops were ever committed, a swift and decisive victory is extremely unlikely. Iran is designed, by geography, population, and strategy, to turn any invasion into a long and grinding conflict. American planners know this, which is why no administration has seriously attempted a ground invasion despite decades of tension. The geography alone makes quick victory implausible. Iran is a fortress of mountain ranges, deserts, and narrow passes. The Zagros and Alborz mountains offer natural strongholds and guerrilla terrain. Saddam Hussein’s Iraq, despite years of brutal fighting, failed to break through the Zagros in the 1980s. Iran’s population compounds the challenge. With more than 85 million people, deeply nationalistic even if critical of their leaders, Iran can draw on a vast pool of fighters. Beyond its standing army and the IRGC, it can mobilize militias like the Basij, who would blend into cities and towns as guerrilla fighters. U.S. experience in Fallujah and Mosul showed how long it can take to root out small groups of determined fighters street by street. Multiply that across a nation of Iran’s size and the prospect of rapid regime collapse fades into fantasy. Even if Tehran were taken, an insurgency could stretch on for years, with constant ambushes, roadside bombs, and sniper fire. Iran’s military posture is also designed for attrition, not parity. It cannot match U.S. firepower in open battle, but it has invested heavily in asymmetric weapons: thousands of ballistic missiles, mobile anti-ship systems, swarms of fast boats and drones, dense layers of air defenses. This is a punishment strategy. Iran can’t stop an invasion, but it can make every U.S. advance costly enough to sap political will. In 2020, Iran showed precision by striking U.S. troops in Iraq with missiles. Its strategy is simple: hold out, inflict casualties, and wait for Washington to lose heart, as North Vietnam did half a century ago. Meanwhile, the 'U.S.' would fight with limits. Nuclear weapons are off the table, and the use of overwhelming firepower is constrained by the risk of inflaming global opinion, wrecking oil markets or provoking Russia and/or China. The U.S. needs to balance military needs with political optics, economic costs, and alliance management, and each restraint slows the pace of operations and gives Iran more breathing room. External powers could make sure the war drags on. China relies heavily on Iranian oil and views Iran as a key partner in its Belt and Road network; Russia sees Tehran as a counterweight to U.S. influence and a lucrative arms client. Neither wants a U.S. victory. They would likely stop short of direct war but could supply advanced air defenses, intelligence, cyber support, and diplomatic cover. An invasion would ripple through the international system, triggering counter-moves that collectively blunt U.S. power. The longer the U.S. stayed bogged down, the more its rivals could bleed it indirectly. Domestic Unrest and the Risk of Civil Conflict A drawn-out U.S. war in Iran would not only drain blood and treasure overseas but also ignite turmoil at home. History shows how unpopular foreign wars reverberate domestically. Vietnam fractured American society, producing mass protests, militant opposition groups, and even deadly confrontations like Kent State. That unrest fell short of civil war, yet it revealed how sustained casualties and stalemates abroad corrode political legitimacy. Today’s America is even more polarized, with surveys showing nearly half of citizens expect civil war within their lifetimes. Against that backdrop, a blunder in Iran would act like fuel poured onto already smouldering divisions. The chain of events is easy to imagine. Casualties mount, flag-draped coffins fill nightly broadcasts, and Iran deliberately plays to U.S. public opinion by showcasing captured troops or delivering a steady drip of losses. At the same time, the economic toll lands hard: sabotage of Gulf shipping pushes oil prices skyward, inflation bites, and federal war spending swells deficits. Ordinary Americans feel the conflict directly through higher costs and financial insecurity, just as faith in government competence sits at historic lows. The atmosphere recalls the late 1960s, but with social media magnifying outrage and polarisation in real time. A replay of the 1960s unrest is the minimum scenario; the maximum is a spiral toward systemic breakdown if certain triggers are pulled. Chief among them would be the return of the draft. Vietnam proved how conscription radicalises opposition, and in today’s fractured landscape, resistance could escalate beyond protest. Would a U.S. Civil War or Defeat Mark the End of the American Empire? A drawn-out Iran war that the U.S. fails to win quickly – especially if it leads to serious internal strife – would likely spell the end of the American Empire as we know it. By American Empire, I mean the United States’ post-WWII role as the predominant global superpower, enforcing a world order through its military alliances, economic might, and soft power. History suggests that when great powers become bogged down in costly conflicts and face domestic upheaval, their era of primacy comes to an end. We can draw parallels to the decline of the British Empire. Britain emerged victorious in WWII but exhausted; then it mishandled the 1956 Suez Crisis (a failed intervention in Egypt) and faced financial ruin. After Suez, it became clear Britain could no longer act as a world police independent of the new superpower, and within years it gave up its remaining colonies. If the U.S. were seen unable to defeat Iran (a regional power) despite massive effort, international perceptions would shift dramatically. Allies might doubt U.S. security guarantees, and adversaries would be emboldened to challenge U.S. interests elsewhere. Political scientist Paul Kennedy famously theorized about “imperial overstretch”, where an empire’s global commitments outstrip its economic base and erode its power. A failed Iran war would be a textbook case of overstretch. In fact, some observers argue the signs of American imperial decline are already evident. One analysis notes that the U.S. lost its subsequent wars in Vietnam, Afghanistan, and Iraq, and even massive efforts in recent proxy conflicts haven't produced clear victories. The inability to decisively prevail, despite unparalleled military spending, suggests a waning of effective power. Empires in decline often respond by over-extending their coping mechanisms, as economist Richard Wolff writes – they undertake more military actions even as their capacity to sustain them diminishes. This produces a vicious cycle of costs and “blowback” that accelerates the decline. In Wolff’s words, “Policies aimed to strengthen the empire… now undermine it.” A U.S. decision to invade Iran could be seen in that light: an attempt to reassert dominance that instead backfires and bleeds the empire dry. If the U.S. became embroiled in civil conflict (even short of full civil war), its ability to project power externally would evaporate. Imagine National Guard units (often key to deployments) busy dealing with unrest in American cities, or a government divided and paralyzed. The rest of the world would naturally adjust to a post-American leadership era. Geopolitically, rivals like China and Russia would seize the opportunity to expand their
