Mural on the walls of the former U.S. embassy in Tehran.The United States and Iran don’t need any help when it comes to not getting along. The institutionalized enmity goes back three decades—sometimes in spite of the people in Washington or Tehran and other times exacerbated by misperceptions of their respective national interests. Iran and the United States, after all, are geographically distant, operate on very different systems, and both carry complex cultural and political baggage.

All of this misunderstanding combines to foster incomplete or false narratives that can take on a life of their own. Here are five of the most damaging myths—from one or both sides—that have facilitated and exacerbated U.S.-Iran hostility.

1.) Iranian Myth: Iran can extend the conflict with America for several years and survive without making major concessions.

Reality: Since 2005, Iran’s nuclear dispute with the West increasingly has evoked memories of the 1980–1988 Iran-Iraq war. There’s infighting within the regime over fears that the country is taking its costly nuclear pursuits too far, much as it did in prolonging the war against Iraq.

Though then leader Ayatollah Ruhollah Khomeini promised victory and the overthrow of Saddam Hussein, he was forced to drink from what he called a “chalice of poison” and accept a ceasefire that won Iran little more than an end to the fighting. Today, the conflict with the West and the United States may look different, but the arguments for perpetuating it are similar. Iranian hard-liners believe they can persevere, seeing justification in high oil prices, America’s problems at home and abroad, and the uncertain long-term sustainability of international sanctions. They insist that time will force America to accept Iran’s nuclear program, acknowledge its regional power and abandon threats of regime change.

When Iran gained a military advantage over Iraq in 1982, senior Iranian officials debated what to do with their edge. Pragmatists advocated for ending the war while Iran had the upper hand, but hard-liners argued that the country could prevail outright. Today, pragmatists warn hard-liners not to underestimate the threats of sanctions and outright war as part of Iran’s nuclear standoff with the West. Since 2005, they have argued, borrowing a line from Khomeini, that Iran should avoid drinking from the poison chalice tomorrow because of bad decisions today.

2.) American Myth: Sanctions are an alternative to war and will, over time, help facilitate Iranian democracy.

Reality: Sanctions have been heavily debated in scholarly and policy circles for years, but many academics are pessimistic, especially when the sanctions are meant to deter a state from doing something it might perceive, rightly or wrongly, as necessary for its survival. A much-cited study of sanctions by three Peterson Institute for International Economics scholars found, as a 2004 World Bank paper summarized, that “Studies of economic sanctions (including trade sanctions or freezing of financial assets) conclude that they are usually unsuccessful.”

Sanctions often have failed to achieve their desired outcome, while impoverishing the civilian population and sometimes leading to government crackdowns. The status quo can remain indefinitely; Cuba is a telling example, as is Iraq in the 1990s and 2000s.

The Iranian government so far has been able to ride out sanctions, supported in part by its enormous energy resources. The latest round of sanctions on Iran’s oil and banking sectors has given them new bite, but they’ve also escalated the stakes for both sides.

Some argue that if sanctions don’t lead the Iranian regime to shut down the nuclear program voluntarily, maybe they will spark pressure from angry citizens. Unfortunately, there is ample evidence that sanctions delay and ultimately impede democratic evolution. The Economist Intelligence Unit 2010 Index of Democracy notes that, of the world’s eighty-eight nondemocratic states, 71 percent have been under economic sanctions. Of the thirty-five states that have transitioned to democracy since 1955, all but one did so without broad economic sanctions. From Cuba to North Korea to Iraq, sanctions have coincided with reactionary elements of a political system digging in while democratic elements weaken.

3.) Iranian Myth: The West is in decline, particularly on the economic front. America’s military is overextended. War on Iran is not a plausible option.

Reality: Within both Iranian and U.S. domestic politics, the hard-liners are influential. In Washington, a confrontational Iran policy is one of the few issues with broad bipartisan support in Congress, as the recent U.S. sanctions on Iran’s Central Bank illustrate. In Tehran, a number of political forces have built their reputations on an anti-American posture.

Hard-liners on each side, confident in their opponents’ weakness and their own ability to prevail through force or threat of force, spark the sort of reciprocal aggression that makes conflict more likely.

But the Iranian end of this escalation is unusual in that it’s based less on the realities of American power than on the regime’s hypothesis: Tehran thinks the United States is declining and therefore will shy away from conflict. The notion of U.S. decline is still questionable, but even if this declinist narrative turns out to be accurate, it might not preclude a U.S. war on Iran. It could even make war more likely.

Historically speaking, global superpowers sometimes have declined peacefully, recalibrating their external behavior to changing times. In other cases, they use force to maintain weakening hegemony. Iranian hard-liners assume America’s political and economic challenges will make it less likely to use military force, but this is only one possible scenario. It’s plausible that American decline might make its leaders more willing to express U.S. dominance through force. It’s also possible that America won’t decline precipitously or at all. Stubborn insistence on the decline narrative could be a huge miscalculation by Iranian decision makers.

4.) American Myth: The problem with Iran is solely its government. Regime change is the antidote that will improve U.S.-Iran relations.

Reality: Washington’s assumption that the root cause of hostility with Iran is the nature of the Islamic Republic itself is simplistic and ahistorical. The regional dynamic created in the aftermath of the Ottoman Empire’s collapse (regional penetration by outside powers, exacerbated by Cold War dynamics) eventually put Iranian strategic goals in direct opposition to the United States, despite some periods of cooperation.

The U.S.-Iran cold war is unique because of the Middle East’s critical impact on the global economy in the twentieth century. This has made the independence of regional powers—Iran or otherwise—a threat to what the United States perceives as its national interests because the impact of Middle East energy resources on the international political economy has been paramount.

Though the domestic priorities and characteristics of Iran’s governments have been wildly different, there has been a notable degree of continuity in Iranian foreign policy. Every political entity in Tehran over the past 150 years has sought foreign-policy independence, economic empowerment, regional preeminence and overall self-sufficiency. Inevitably, this clashed with Washington’s long-standing strategic priorities in the Middle East: a regional-security framework built around pro-American client regimes to keep oil prices stable and facilitate U.S. preferences.

Signs of future conflict were visible before Iran’s 1979 revolution. The shah’s hawkish oil policies in the 1970s, and his direct intervention into the affairs of regional Arab states such as Iraq and Oman, are prime examples. These signs became more distinct as the incompatibility of American and Iranian core national interests grew and intensified following the revolution. Because of the region’s importance to the global economy, security conditions in the Middle East have long proved dysfunctional when an independent posturing of a regional actor challenges superpower preeminence—regardless of the prevailing political system in Tehran or political party in Washington.

Thus, the U.S.-Iran conflict is not a clash of civilizations or ideologies but rather a clash of core national interests, with a regional power trying to be independent in a subsystem traditionally ruled by a superpower. This does not mean that a secular, democratic Iran would have the same problems with the United States. Yet, this unique triangulation will not change, even if Iran evolves into a secular democracy: the Middle East’s historical dominance in the global energy market, Washington’s stated national interest in maintaining primary control of the region, and Iranian foreign-policy imperatives of independence and self-sufficiency all will remain. As Stephen Walt has argued, if this clash remains unresolved, conflict of some kind will continue to be a feature of regional politics.

5.) Shared Myth: The status quo U.S.-Iran cold war is sustainable.

The Reality: America’s decade-long wars in the Middle East have engendered a degree of political realism in Washington. The inconclusive nature of its combat withdrawals, the global financial crisis and the ongoing flux of the Arab Spring have pushed U.S. strategists to focus on what is viable. Still, occasional efforts at sustained diplomacy on Iran’s nuclear program by both parties have not resolved the larger political conflict. Right now, the process mostly serves to maintain the same old rivalry.

U.S. and Iranian strategies are stuck in the status quo, but the world around them is changing. From Egypt to Pakistan, longtime U.S. allies surrounding Iran are increasingly at odds with Washington, each for its own reasons. Most notably, some Israeli leaders are threatening a military conflict with Iran, a mess that the United States might have to clean up.