After Pearl Harbor, public opinion swung heavily in support of the war.
"We should pay much attention to the fact that people's opinions swing a lot - a lot," he said.
Following the Chernobyl disaster, public opinion swung against the power plant.
There is also the worry, others say, that popular opinion in poppy growing areas could swing back toward the Taliban.
When new information about a candidate is introduced, voters' opinions can swing wildly.
"As that sinks in, opinion is swinging to our side."
If there's friction with Earth during the building of the stations, public opinion on the Moon may swing back.
"The more Cubans are seen as normal human beings - that the father is a decent guy - public opinion will swing," he said.
By then, however, public opinion had swung strongly against her.
If that happens, anti-American opinions in the Arab world might swing, these rulers hope.