Trump’s New Way of War: Beyond the Powell Doctrine

The Shifting Sands of American Military Doctrine: Iran, Venezuela, and the End of the Powell Doctrine

When bombs began falling on Iran this weekend, most Americans were as surprised as the rest of the world. The U.S. Force posture in the Middle East had been building in the preceding weeks, but negotiations between Washington and Tehran were still underway. Even as the U.S. Military readied for an attack, the Trump administration obscured the exact objective. There was remarkably little national debate, scant discussion with U.S. Allies, and no vote in Congress about the desirability of conflict. Two days into the war, administration officials have yet to articulate a specific vision for how it will end. Instead of employing decisive force, U.S. President Donald Trump is prioritizing flexibility. This stance reflects a new way of war—visible across multiple Trump interventions, from the Red Sea to Venezuela—that inverts traditional thinking on the use of force.

in many ways, Trump’s use of force is the anti–Powell Doctrine. Developed during the Gulf War (1990–91) by General Colin Powell, who later served as secretary of state, the Powell Doctrine held that force should be employed only as a last resort, after all nonviolent means have been exhausted. If war is necessary, however, it should proceed in pursuit of a clear objective, with a clear exit strategy, and with public support. It should employ overwhelming, decisive force to defeat the enemy, using every resource—military, economic, political, social—available. Derived from the lessons of Vietnam, the approach was designed to avoid protracted conflicts, high death tolls, financial losses, and domestic divisions. As Powell later wrote, military leaders could not “quietly acquiesce in halfhearted warfare for half-baked reasons that the American people could not understand or support.”

The Powell Doctrine, building on criteria established in the 1980s by Defense Secretary Caspar Weinberger, spurred debate from the start. Some critics thought the all-or-nothing approach to war would preclude the tailored use of force to achieve modest but still vital goals. Supporters of the doctrine, however, saw continued interventions, such as those undertaken by the Clinton administration in Somalia, Haiti, and the former Yugoslavia, as a misuse of military power that risked failure or quagmire.

Testing the Doctrine: Afghanistan and Iraq

The U.S. Invasions of Afghanistan in 2001 and Iraq in 2003 were key tests of the Powell Doctrine. The George W. Bush administration sought to apply the doctrine in both cases. It declared war only after the Taliban and Iraqi leaders, respectively, ignored U.S. Demands, and after the president spent considerable political capital to persuade Americans that the decisions to move to war were wise. The administration’s stated objectives were clear: to eliminate the safe haven the Afghan government was providing al-Qaeda and to rid Iraq of weapons of mass destruction. Congressional authorization was as well secured in both instances. In Afghanistan, U.S. Forces combined air attacks with support for fighters in the Northern Alliance, which entered Kabul and overthrew the Taliban. In Iraq, 160,000 U.S. Troops launched a ground invasion to topple the regime. The planned exit strategy involved turning governing institutions over to exiles, local leaders, and domestic security forces, after which American troops would come home.

However, things did not go according to plan in either case. Attempting to avoid prolonged conflicts brought them about anyway. The wars proved extraordinarily costly and deeply divisive, and their objectives seemed only to shift over time. Whether the interventions’ problems came from a misapplication of the Powell Doctrine or from a fundamental misconception of the approach itself, the shadows of Afghanistan and Iraq have colored every U.S. Military intervention of the past two decades, including the current war in Iran.

The New Force: Trump’s Inversion

This new approach to war began forming in Trump’s first term and has solidified in his second. Trump ordered missile strikes against Bashar al-Assad’s regime in Syria, continued U.S. Military operations in Iraq and Syria against the Islamic State (also known as ISIS), and authorized the killing of Iranian General Qasem Soleimani. Further actions included a war against the Houthis in Yemen, strikes on Iranian nuclear facilities, and an invasion of Venezuela to remove Nicolás Maduro, culminating in the recent major operation in Iran.

These operations depart significantly from more traditional ways of employing force. The Powell Doctrine holds that war should be a last resort, employed only after political, diplomatic, and economic means have failed. Presidents George H.W. Bush and George W. Bush both issued public ultimatums before initiating hostilities.

Trump’s approach, however, has been to use ambiguity as a source of advantage, to catch opponents off guard. The 2025 and 2026 U.S. Attacks on Iran, for instance, took place even as negotiations were ongoing. His administration issued no public ultimatums to Soleimani or Maduro. For Trump, force is not a last resort, but rather one of several tools available to increase leverage, maximize surprise, and produce outcomes.

Public Support and Clear Objectives: Abandoned?

Another element of the Powell Doctrine that Trump seems to have abandoned is the emphasis on public support. The Powell Doctrine views the Vietnam-era protests against American intervention as a cautionary tale. If an objective is important enough for Americans to fight for, the thinking went, the people in whose name the fighting takes place had better support it. Establishing such support generally requires the president to make a case, frequently and over the course of months. Congress is expected to demonstrate its own approval through a vote to authorize force after extended debate.

Where the Powell Doctrine calls for clarity, Trump instead prizes flexibility.

However, not a single conflict during Trump’s presidencies has been preceded by a campaign to win public support, and Congress has not voted to authorize any of them. Instead, each conflict began suddenly and followed an unpredictable course. Rather than lay out a case for each war, the president often insisted he hoped to avoid it. His administration prioritized surprise, for example, claiming that a Caribbean military buildup was to stop drug boats, not to prepare for a direct regime change operation in Venezuela. Congress was largely sidelined. Iran today presents an even more ambitious regime change operation, but in last week’s State of the Union address, Trump talked about it in only a few sentences. The scale and stakes of the war make the administration’s seeming disregard for public debate all the more remarkable.

The Trump administration has also avoided articulating clear objectives for its use of force. When announcing that war with Iran had begun, the president said that the objective was “to defend the American people by eliminating imminent threats from the Iranian regime,” even though Tehran was neither enriching uranium nor in possession of missiles capable of reaching the United States. A day into the attacks, Trump wrote on social media that bombing was aimed at achieving “our objective of PEACE THROUGHOUT THE MIDDLE EAST AND, THE WORLD!” He has said both that the goal is regime change in Iran and that he is planning to negotiate with the leadership that replaces the supreme leader. Trump similarly said at first that pressure on Venezuela was necessary to stop drugs and gang members from entering the United States, before later explaining that the goal was to bring Maduro to justice, to take back oil stolen from the United States, and that the operation was consistent with a new corollary to the Monroe Doctrine. What precisely Americans are fighting for in each country, and how they will know whether they attain that end, remains unclear.

Where the Powell Doctrine calls for clarity, Trump instead prizes flexibility. By claiming multiple and often vague objectives, the president retains the ability to stop the fighting without admitting defeat. This, rather than obvious victory, is his exit strategy. When announcing attacks on the Houthis, Trump said, “We will use overwhelming lethal force until we have achieved our objective,” with the objective allegedly being to end Houthi attacks on American vessels in the Red Sea. The Houthis, Trump said later, would be “completely annihilated.” A month into an expensive and only partially successful bombing campaign, however, the administration cut a deal with the group to end its attacks.

Finally, Powell’s dictum holds that the United States should employ overwhelming, decisive force in pursuit of its objective, defeating the enemy as swiftly and soundly as possible. Trump’s approach, favors short, sharp military actions that employ only particular kinds of force, especially airpower and special forces, almost always excluding conventional ground forces. If the price of regime change in Iran is the large-scale deployment of ground forces, Trump has made clear through past action that the United States will not pay it. It will instead settle for less.

Good Enough? The Limits of the Trump Approach

In some ways, the Trump response to the Powell Doctrine has served recent history better than a dogmatic application of the original. Following the limited use of force against the Houthis with a bilateral agreement produced a better outcome than ignoring the attacks on U.S. Shipping. It was also better than using pure military force, as Saudi Arabia and the United Arab Emirates had attempted for years. Likewise, the world is better off without Iran’s nuclear sites at Fordow and Natanz, and without Soleimani running the Islamic Revolutionary Guard Corps. The jury remains out on Venezuela, but it is still possible that a democratic transition occurs and the country avoids a descent into domestic chaos. Short, sharp uses of force that preserve flexibility in decision-making, leverage ambiguity and surprise, minimize the chances of quagmire, and end with a “good enough” outcome might be the best approach to many cases.

They are likely not the best approach to all cases, however, and the limits of Trump’s way of war may soon be clear. The attack on Iran represents the most ambitious of Trump’s foreign policy gambits to date. Forcing regime change in a country that is much larger and more populous than Iraq or Afghanistan, through an operation with no ground component and no obvious domestic allies, and in the face of an entrenched security apparatus, will be extraordinarily difficult. The range of nightmare scenarios—from an IRGC-led military dictatorship to a descent into domestic chaos—is wider than the happy possibility of a democratic uprising.

Here, the president’s flexibility and ambiguity might show the way forward. If the United States and Israel are unsuccessful in toppling the Islamic Republic of Iran, if U.S. Forces take significant casualties, if the American public grows tired of the conflict, or if the alternative to continued regime rule looks even worse, Trump could stop the fight. By claiming that the objective was, from the beginning, to simply weaken Iran and to ensure that it does not obtain a nuclear weapon, the president could, and likely would, declare victory.

In so doing, the president would upend one last Powell maxim: the Pottery Barn rule. Before the invasion of Iraq, the general cautioned, “You break it, you own it.” In the effort to break the Iranian regime, Trump has already telegraphed that the United States will not own the aftermath. Should it collapse, the Iranian people will necessitate to pick up the pieces. If it endures, Washington will wrap up the fight and move on to other priorities. Such a scenario would demonstrate one more limitation of the Trump approach: it does not pave the way for long-term peace but postpones conflict to another day.