(Bloomberg Opinion) -- If talks in Singapore between President Donald Trump and North Korean leader Kim Jong Un conclude with anything short of a collapse, Trump will hail it as a great historical achievement. That’s fair enough, and he'd probably get a boost in the polls.
Yet history shows that public-opinion gains for presidential foreign-policy successes usually are short-lived.
In May, 2011, President Barack Obama orchestrated the killing of Osama bin Laden, the architect of the terrorist attacks of Sept. 11, 2001. Bin Laden was public enemy No. 1 to most Americans, and had eluded capture for almost a decade.
Obama's approval rating rose by about 6 to 8 percentage points, polls showed. But the effect lasted only for a couple of months.
In 1978, in act of forceful and skillful diplomacy, President Jimmy Carter prevailed on Egypt and Israel to set aside three decades of hostility by signing the Camp David peace accords. The Washington Post showed his approval rating soaring by 11 percentage points right afterward. It soon fell back, and seven weeks later Republicans scored gains in midterm elections over Carter’s Democratic Party.
Never was the ephemeral political impact of foreign-policy achievement more evident than the experience of President George H.W. Bush in 1991. He successfully led "Operation Desert Storm," an international military assault that drove Saddam Hussein’s Iraq out of Kuwait in 42 days with just 300 coalition casualties. Later that year came the dissolution of the Soviet Union, America's archenemy for almost half a century. Most historians have awarded the Bush administration high marks for managing this delicate situation.
Bush's approval skyrocketed to 89 percent in polls taken immediately after the liberation of Kuwait. The next year, he lost his bid for re-election.
His son, President George W. Bush, fared better in narrowly winning a second term in 2004, a year after leading the invasion of Iraq. Then his popularity, too, began a long, steady fall.
That didn’t happen to President Franklin D. Roosevelt, who won his third and fourth terms while World War II raged. But that’s a special case.
President John F. Kennedy’s experience can be thought of as the exception that proves the rule. His approval rating rose after the Cuban Missile Crisis of 1962, a tense standoff that ended when the Soviets withdrew their nuclear weapons from Cuba. Days later, Kennedy’s Democratic Party did not suffer the customary losses in midterm elections, though political historians still debate whether that was due to the Cuban crisis.
Kennedy also enjoyed rising presidential approval after the Bay of Pigs invasion of Cuba failed to overthrow Fidel Castro. Kennedy won public accolades for candor by forthrightly taking responsibility for the fiasco.
If the Singapore talks end badly, there's little danger of that occurring.
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