Richard W. Coughlin is a professor of Political Science at Florida Gulf Coast University where he teaches courses in U.S. Foreign Policy, International Security, and Comparative Politics.  Coughlin received his Ph.D. in Political Science from Syracuse University.  His academic articles have appeared in The Journal of Political Science Education, Crossings, Latin American Politics, Critical Sociology and New Political Science.  Shorter think pieces have appeared in Foreign Policy in Focus and E-International Relations. The following interview is drawn from the article  “The Carter Doctrine and the Limits of Liminal Conflict in the Persian Gulf,”,  which appeared in E-International Relations on April 2, 2026.

Gulan: Your article revisits the Carter Doctrine as a cornerstone of U.S. strategy in the Persian Gulf. Yet, in 2026, American responses to repeated tensions—whether maritime incidents, proxy activity, or regional escalation—appear increasingly calibrated and restrained. Are we witnessing a quiet shift where the doctrine survives in rhetoric but no longer operates as a true guide to U.S. behavior on the ground?

Dr. Richard W. Coughlin:  Excellent question.  I think of the Trump administration’s blockade of the Strait of Hormuz and its recent boarding of an Iranian cargo ship (on April 21).  It seems clear to me that the U.S. is unwilling to accede that it has lost control over the strait of Hormuz and so it asserts a secondary blockade, even though that control subverts the intention of the Carter Doctrine, which was to guarantee the  circulation of crucial energy resources.  Now, of course, the U.S. is blocking that circulation. This may be indicative of the fact that the U.S. has renounced the role of acting as a guardian for global capitalist circulation. 

It may also reflect the posture of the U.S. as a regional rather than global power, which the Trump administration articulated in its 2025 National Security Strategy of the United States of America.  This document underscored that the U.S. primary sphere of influence is in the Western hemisphere, not Eurasia.  If all this is the case, then why blockade in the first place?  Here my responses are speculative in nature.   If Iran can weaponize geographical choke points, then so can the U.S.  Indeed, as U.S. political scientists Henry Farrell and Abraham Newman have argued, the U.S. has been weaponizing interdependence ever since the war on terror.  But now the tenor of this weaponization may be changing.  The U.S. may be less interested in asserting power and security across Eurasia and more inclined to extort it. 

Yet all of this bumps us against systemic constraints on U.S. capacity – that the blockade would undermine the world economy and negatively impact Americans and thereby the political standing of the Trump administration.  These are the margins in which the Trump administration is currently pursuing its policy objectives.  This suggests that the U.S. cannot maintain this posture for very long.  After having endured U.S. and Israeli airpower while retaining much of its missile and drone capacity, the Iranians may be willing to outwait the U.S. if the blockade persists or out-escalate the U.S. if the bombing resumes.  

In either case, the Carter Doctrine becomes eviscerated. It is telling, in this regard, how little the Carter Doctrine is named, either by the administration or in media commentary on the war.  Media coverage in the United States remains fixated on statements and counterstatements of the Trump administration.

Gulan: You describe “liminal conflict” as a space deliberately situated between war and peace. Looking at recent dynamics—U.S.–Iran exchanges, Israeli shadow operations, and militia activity across Iraq and Syria—does this ambiguity now represent the preferred strategic environment for major powers, allowing them to escalate without triggering the costs of full-scale war?

Dr. Richard W. Coughlin: Drawing on the experience of Ukraine, my view here was that the space of liminal conflict is becoming exhausted by the growing capacity of non-great power adversaries to fight back.  A key dynamic here is the asymmetry of military conflict – expensive great power weapons systems are increasingly countered by cheap drones and ballistic missile systems.  The geographic mobility of these weapons means that liminal war can no longer function as well to achieve bounded territorial objectives.  For example, the U.S. cannot approach Iran with ships and troops without becoming vulnerable to drone and missile strikes.  Its capacity to project power has been stymied.   

More generally, the new technologies of war limit the options of liminal war and therefore limit the ability of the United States and other great power actors to assert control over key strategic spaces.  Historically, the  U.S. policy flexible response embraced by the Kennedy administration sought to overcome the limits of Eisenhower era reliance on mass retaliation and covert operations as the major instruments of U.S. foreign policy.   

Flexible response certainly did not end with the Vietnam War but made a comeback with the advent of the Revolution in Military Affairs (RMA) – the application of information technology to warfighting.  What the development of drone warfare reveals is how widely this technological capability has been diffused with the effect of leveling the military playing field.  As a consequence, liminal conflict is becoming increasingly restricted to the use of proxy forces to shape the strategic environment in which the U.S. and Israel operate.  This is a force that is increasingly exercised on the margins of geopolitics.   I would characterize these types of engagements as entropic engagements that are incapable of founding a new order and decreasingly capable of upholding the existing order.  All of this, I think, is characteristic of the deepening of multipolarity in world politics, characterized by the diminished capability of security actors to impose order.

Gulan: The Carter Doctrine was built on the premise that securing Gulf energy resources justified decisive military commitment. However, despite attacks on oil infrastructure and ongoing instability, Washington has shown increasing reluctance to escalate. Does this reflect a deeper structural shift—where energy security no longer carries the same strategic weight—or is the United States simply adapting its methods within the same overarching framework?

Dr. Richard W. Coughlin: In the heyday of the Carter Doctrine the United States was much more dependent on oil from the Persian Gulf.  In 1990, 30% of U.S. crude imports came from the Persian Gulf.  Today, that number is down to 8.15%, according to the American Petroleum Institute.  President Trump has openly declared that the U.S. doesn’t need oil from the Persian Gulf.  Vulnerability to the Persian Gulf supply crunch is uneven.  Americans are paying higher energy prices.  Countries in South Asia, Southeast Asia, and East Asia are both experiencing higher prices and growing resource scarcities, which are obliging them to partially shut down their economies.  The medium-term consequences of all this are a global recession brought about through disruptions in global supply chains. Longer term, states are going to make themselves less dependent on global energy and food systems that are increasingly subject to geopolitical volatility.  For the United States, there is a certain irony here.  The Trump administration has declared the U.S. as a petro-power, but its foreign policies are hastening the shift from fossil fuels to renewable energy. 

What explains this?  To answer this question, one has to shift levels of analysis.  Structural conditions and attributes of different state actors are always mediated by the complexion of specific political regimes.  The second Trump administration is less constrained by the policy professionals comprising the U.S. national security establishment and which provided operational stability from one administration to the next.  The second Trump administration cut the size of the National Security Council by more than half since taking office. Substituting for expertise are the intuitions of the President and the advice he received from the Israeli prime minister on launching an armed assault on Iran in the face of negative assessments of the plan from top foreign policy officials. 

On the other hand, structural factors do intervene in the U.S. decisions to engage in the use of force.  Isolated from the Old World of Eurasia, the U.S. has historically acted in the world through offensive power-projection policies.  The Carter Doctrine is an artifact of this forward-leaning posture.  Now the forward leaning posture is becoming increasingly tributary and rent-seeking in character reflecting how the Trump administration mediates existing structures of the current international state system. Whether the U.S. can maintain this posture amidst growing debt, worsening economic conditions and rising domestic anti-war sentiment is indeed an open question. 

Gulan: One of the most notable features of current tensions is what has not occurred: despite repeated provocations, the United States has avoided targeting core Iranian infrastructure such as electricity grids, dams, or critical economic nodes. In your view, is this restraint a sign of strategic maturity shaped by the risks of liminal conflict, or does it reveal uncertainty in Washington about how to define—and achieve—victory in such an environment?

Dr. Richard W. Coughlin: The U.S. went through a well-defined repertoire of actions to destabilize Iran.  It imposed sanctions, intensified using the dollar as reserve currency. Then it proceeded to politically destabilize Iran. Trump told Fox news in April that the U.S. had given Iranian Kurds “a lot of arms” – a claim that Kurdish Iranian military forces rejected.  Still, destabilization is part of the U.S. recipe for attacking unfriendly regimes.  Then it opted for the use of direct military force, hoping to collapse the regime. When this didn’t work, the U.S. and Israel banked on escalating the severity of strikes against Iran. When Iran countered with strikes on Israel, U.S. military bases in the Persian Gulf, and key infrastructure within the Gulf Coast States, the U.S. discovered that it did not possess escalation dominance with Iran. 

There is a certain prudence in this reckoning, reinforced by rising gas prices and a plummeting stock market in the U.S.  The economic costs of victory are too high and the Trump administration's argument that the public should absorb the economic costs of escalation for the sake of security gains has already been rendered threadbare by the economic costs of Trump’s tariff policies. The reflex of the U.S. is to play for time and defer strategic defeat at the hands of the Iranians. This has become evident in the way in which Trump has oscillated between brandishing threats and extending ceasefires.  Your point that Washington does not know how to achieve victory rings true here.  The corollary of this point is that it also wants to avoid a catastrophic outcome to the conflict.  Like the U.S. in Vietnam, it defers defeat into the future. 

Gulan: In fragmented arenas like Iraq, where state institutions, militias, and external powers operate simultaneously, liminal conflict appears to blur the lines of authority and control. Does this environment ultimately empower local actors to shape outcomes more independently, or does it lock them into a cycle where their agency is constrained by larger geopolitical competition?

Dr. Richard W. Coughlin: The key point here both in Iraq and across the region is the stability of states.  In recent history, state collapse has unleashed local actors from constraints geopolitical competition by radically altering the playing field.  Iraq is a key example of this where the U.S. destruction of the Baathist regime resulted in the establishment of an autonomous Kurdish region in Iraq. The subsequent combined collapse of the Assad regime (albeit partial) in Syria and post-Saddam regime in Iraq gave rise to the ISIS Islamic caliphate. The U.S. mobilized Kurds in Syria and Iraq to fight ISIS, a process that led to the establishment of another autonomous Kurdish zone in Eastern Syria.  

The general pattern – state collapse followed by the expansion of the independent actors – may be replayed in Iran.   The U.S. and Israel believed that they could administer a knockout blow to the Iranian state with the commencement of their air war on February 28.  The U.S., Israel, and Iran agreed to a cease fire April 12, which President Trump extended on April 21. This suggests reluctance to escalate military attacks on Iran.  Attempting to wreck the Iranian state would result in widespread collateral damage inflicted by Iran on the region, threatening its economic viability.  The existing geopolitical order in the Persian Gulf remains tenuously in place.  In this context, the typical pattern for local actors is to operate in the interests of the more powerful state actors. Thus, Iraqi Shiites carry on strikes on U.S. targets in the Green Zone of Baghdad and other U.S. military installations.  Iranian Kurds based in the Kurdish Iranian zone of Iraq may be armed by the CIA for renewed attack on Iran. 

But across the region, there are tipping points that can be activated by state collapse.  Geopolitical competition does indeed set limits to liminal conflict, but these limits could very well be blown apart if conflict in the Persian Gulf escalates to the point where the U.S. and Israel attempt to destroy the Iranian state and Iran reciprocates by wrecking the economies of the Gulf Coast states.  At that point, geopolitical limits turn into geopolitical turmoil, which provides local actors with new possibilities for action.  

Gulan: Much of your analysis suggests that liminal conflict is not a temporary phase but a structural feature of contemporary geopolitics. Looking ahead, do you see any realistic pathway out of this “in-between” state in the Persian Gulf—whether through diplomacy, deterrence, or regional realignment—or are we entering a prolonged equilibrium where instability itself becomes the system?

Dr. Richard W. Coughlin: When Donald Trump accepted Iran’s 10-point plan as an acceptable basis of negotiations between Iran and the United States, he was the telegraphing  the incapacity of the United States to force Iran to accept its negotiating position.  Since then, the United States has been trying to walk back this concession and reimpose its 15-point bargaining framework with U.S. naval blockade and renewed threats of destroying Iranian infrastructure.  Yet, if it attempts to impose its will through force, the region could experience widespread and long-term destruction.  The damage that has already been sustained in the region demonstrates to the Gulf Coast states that they cannot, in any case, rely on American security assurances.  In the long term, U.S. influence and power projection into the region are bound to wane.  As this occurs, regional powers will be increasingly able to negotiate regional security agreements. This is what the deepening of multipolarity looks like in international politics.  

The primary difficulty, however, in any regional security arrangement would be the place of Israel.  Resolution of the Israeli Palestinian conflict could pave the way toward Israeli membership in a regional peacekeeping organization. Failing that, a softening of the U.S. support and military aid to Israel – quite possible given Israel’s diminishing levels of domestic support in the U.S. – could circumscribe Israel’s territorial ambitions and lead toward greater regional stability. 

Gulan: In the Kurdistan Region of Iraq, we see a particularly complex case: a semi-autonomous entity navigating relations with Baghdad while simultaneously balancing pressures from Tehran, Ankara, and Washington. In this sense, could the Kurdistan Region be understood as existing in a form of political and strategic liminality in its own right? And does this position ultimately provide Erbil with room for maneuver, or does it leave it more exposed during moments of regional escalation?

Dr. Richard W. Coughlin: One way to think about this question is to compare the KRG with Rojava.  The latter was a space to which the PKK fled and where they succeeded in disseminating its egalitarian ideology. This generated the political forces that led to the Kurdish seizure of power across the region, forcing Baathist leaders from power and then militarily repulsing ISIS militants. In this latter context, the Rojava Kurds were patronized by the United States because they were useful in effecting the defeat of ISIS.  But in no sense did Rojava enjoy long term security guarantees from the U.S.  After the defeat of ISIS, the first Trump administration greenlighted Turkey’s invasion and occupation of the region. 

In comparison, Erbil enjoys greater stability.  This is because the KDP is not an antisystemic power thus it is not as threatening to existing state powers in the region.  The KRG has been able to stabilize its relations with Iraq and avoid antagonizing Iran, Turkey, and the United States.  In this sense, the KDP has been able to insulate itself from liminal conflict to a much greater degree than Rojava and then use its resource base to pursue a regional project of economic development.  The strategic liminality enjoyed by the KRG stems from its capacity to blend into its surrounding geopolitical environment.  But it is still subject to shifts in this environment.  The most pronounced of these shifts is the ongoing expulsion of the United States as key power in the region, as evidenced by the collapse of its key strategic doctrine - the Carter Doctrine.