Unlock the White House Watch newsletter for free
Your guide to what Trump’s second term means for Washington, business and the world
The writer, president emeritus of the Council on Foreign Relations, is the author of ‘War of Necessity, War of Choice’
Wars tend to fall into one of two categories, either necessity or choice. Wars of necessity involve the most vital national interests and require the use of military force after other policy choices (including inaction) are deemed inadequate. By contrast, wars of choice tend to involve less than vital interests and are fought even though other policies — including diplomacy, sanctions, covert action and deterrence — could arguably have been employed.
Wars of necessity include Ukraine’s response to Russian aggression in 2022. The US intervention following North Korea’s invasion of South Korea in 1950, as well as Washington’s response to Iraq’s 1990 conquest of Kuwait, were necessary. Ousting the Taliban in Afghanistan after 9/11 also qualifies, given the possibility the Taliban would have allowed future terrorism to emanate from its territory. Wars of choice are not per se a mistake. But they do place great pressure on leaders to demonstrate results that justify their decisions and the inevitable costs. Vietnam and America’s 2003 war in Iraq were wars of choice. So was Russia’s invasion of Ukraine. The current war against Iran is a textbook war of choice.
America did have other viable options, above all diplomacy, especially as no convincing case has been made that an imminent threat had to be dealt with militarily. The contrast between Washington’s near-unlimited willingness to compromise and demonstrate patience when it comes to persuading Russia to end its aggression against Ukraine and its unrealistic demands and lack of patience with Iran in the run-up to this war is as stark as it is telling. Ukraine’s offer to help defend against Iranian drones while Russia reportedly provides intelligence to Iran only makes the double standard worse.
The debate over whether the Trump administration and Benjamin Netanyahu’s government in Israel were right to have launched this war when they did is raging. It will (and should) continue long after the guns are silent. But the question now is: when and how should this war be brought to an end?
The argument for America continuing the war is to further reduce Iran’s military capabilities and to bring about a less radical leadership. The problem is that military efforts face the reality of diminishing returns and interfere with the emergence of a coherent leadership willing and able to end the fighting. The prospects for regime change leading to a democratic Iran are poor.
Meanwhile, the costs to the US and to President Donald Trump are mounting: dead service members, attacks on allies in the region, shortages of defensive systems, spiking energy costs, falling stock markets and poll numbers — not to mention the weakening of Washington’s ability to deal with the Chinese threat in the Indo-Pacific and the Russian menace to Ukraine and Europe.
On Friday, Trump called for Iran’s unconditional surrender and a say in choosing its next leader. But the US must instead think realistically about terms for ending the war, no matter what the political outcome in Iran. Ironically, doing so will probably require returning to many of the issues US officials considered and rejected before the conflict began: what scale of Iranian nuclear programme is it prepared to tolerate? What, if any, constraints should be placed on Iran’s ballistic missiles, its support for proxies and terrorism, and repression of its people? What, if any, relief from economic sanctions should be offered as an inducement?
Those who now dismiss such questions need to keep in mind that the consequences of ignoring them would be continued conflict, with all that would entail. The US would also have to be willing to press Israel to stop the war, something it may resist as it pursues what it sees as a chance to solve the Iran problem for good. That said, Trump is hugely popular in Israel, and Netanyahu cannot afford to alienate him in the months before a crucial election.
Finally, Iran’s new leaders — whoever they turn out to be — will also have reasons to end the war: to preserve what’s left of their military and economy, to consolidate political authority and ensure the country stays intact. However, Iran may hold off until the US is asking for peace in the hope of striking a better deal. They would have to answer the same questions as the US regarding their security policies and sanctions, and declare what they would require to allow tankers to start moving freely again through the Strait of Hormuz in a way that insurers deem safe.
If all this sounds familiar, it should. Ultimately, both sides will have to return to the issues that led to war in the first place. The question is when: it only takes one side to start a war, but here it will take all three to end it.