In July 1988, faced with bleak prospects in its war with an American-backed Iraq, Ayatollah Ruhollah Khomeini, the founder of the Islamic Republic, decided reluctantly to accept a cease-fire and end the conflict.

“It’s like drinking from a chalice of poison,” he told Iranians. But the survival of the young Islamic Republic depended on swallowing.

His successor as supreme leader, Ayatollah Ali Khamenei, now faces a similar decision. But having led the country since 1989 and rebuilt it as a regional and nuclear power, it is by no means clear that he will make the same choice.

At 86, with much of his life’s work in ruins around him, he may prefer martyrdom to the surrender that President Trump and Prime Minister Benjamin Netanyahu of Israel are demanding of him.

Iran’s first response was defiant. “The Islamic Republic of Iran is resolved to defend Iran’s territory, sovereignty, security and people by all force and means against the United States’ criminal aggression,” the foreign ministry said in a statement.

Iran has already launched a serious barrage of missiles on Israel. It may, as it has warned, attack some of the 40,000 American soldiers in the region.