Trump’s hawkish advisers and the hard-liners in Tehran could easily become mutual enablers in pushing a crisis up the escalatory ladder. The idea that the conflict is inevitable can produce momentum of its own, as can the sort of hubris that led to a disastrous war in Iraq in 2003. And should Iran abandon the deal altogether, the odds of conflict will grow larger still.

An escalating conflict brings with it an increased risk of significant collateral damage. Fissures between the U.S. and our European allies are widening as a result of our withdrawal from the nuclear deal with Iran, our subsequent pressure campaign, and our erratic saber-rattling. We’re also eroding the long-term utility of economic sanctions with our reckless unilateralism. Even our closest partners have begun to talk publicly about reducing exposure to the American financial system as a hedge against U.S. economic pressure.

We’ve seen coercive diplomacy succeed with Iran—this is not how it works.

We’re the two negotiators who led the secret bilateral talks with the Iranians that paved the way for the interim and comprehensive nuclear deals between Iran and the so-called P5+1, the five permanent members of the UN Security Council and Germany. The United States built broad international pressure to bring Tehran to the table—the political leverage of an international community united in its determination to prevent Iran from developing a nuclear weapon; the military leverage of a credible threat of force; and the economic leverage of sanctions that ultimately produced a 50 percent drop in Iran’s oil exports and in the value of its currency.

That pressure was necessary but not sufficient, because pressure is not an end in itself. It was coupled with a realistic aim—a sharply constrained, tightly limited, and closely monitored civilian nuclear program—and a willingness to engage directly with the Iranians, not through empty summitry but over many months of arduous negotiations.

Now, after more than a year of coercion, with no capitulation or implosion in sight, and no shortage of risks on the horizon, it’s time to take diplomacy seriously again. That means going beyond the repetition of terms the other side won’t ever accept. The best way forward for the Trump administration is to signal privately that its maximalist demands are not carved in stone and pursue a more realistic agenda on nuclear issues. That starts with working to extend the nuclear deal’s timelines, and recognizing that further sanctions relief will be necessary to encourage Iranian acceptance; it means talking quietly about securing the release of Americans detained in brutal Iranian prisons; it means probing for possible understandings on Iran’s ballistic-missile programs; and it means encouraging dialogue on the wars in Afghanistan and Yemen, where Iran will be a player in any eventual settlement.