New Delhi, April 16 -- BE GRATEFUL FOR small mercies. The ceasefire between America and Iran holds. Talks that began in Islamabad last weekend may soon resume. Though the Strait of Hormuz is closed, oil markets are no more spooked than they were. And while economic damage is gradually spreading globally, a deep Hormuz-induced recession could yet be averted.

But small mercies are not enough. If they are not to return to a futile war, America and Iran will have to ensure the ceasefire produces a lasting peace, by opening the strait and settling their dispute over Iran's nuclear programme. That will require compromise and a willingness to grapple with complexity that has eluded both sides-especially President Donald Trump.

The search for p...