Elliott Abrams, a senior fellow for Middle Eastern Studies at the Council on Foreign Relations, was an assistant secretary of state in the Reagan administration and deputy national-security adviser in the George W. Bush administration.

American interests and allies in the Persian Gulf are threatened. What’s needed is a clear and tough statement right from the top, so the president starts making speeches. What does he say?

That depends on whether it’s Jimmy Carter in 1980 or Barack Obama in 2012. Jimmy Carter in 1980 was a lot tougher.

Nineteen-seventy-nine had been a year of American setbacks around the globe. Before the year began, Cuban troops were already roaming Angola, and a pro-Communist regime ruled Ethiopia. In 1979 the Sandinistas seized power in Nicaragua, a coup put leftists in charge in Grenada, the Soviets invaded Afghanistan, the Shah left Iran in January, and in November mobs captured the U.S. Embassy and took more than 60 American hostages. All this was a shock to Carter and his followers, who had come to office seeking to junk the perceived hard line of the Nixon and Ford administrations. In January 1977, U.N. Ambassador Andrew Young had said the Cubans were a "force for stability" in Angola. In May of that year, President Carter had criticized the "intellectual and moral poverty" of our past policies and said, "we are now free of that inordinate fear of Communism" that had previously distorted our foreign affairs.

In response to the terrible events of 1979, Carter changed his tune...