There was a memorable scene in the television series The West Wing when the make-believe President was being strongly advised to give the go-ahead for an assassination.
The target was a terrorist known to be behind the loss of American lives. The President, a liberal Democrat, wrestled with his conscience and, as the opportune moment approached, told his chief of staff exactly why what he was being asked to do was morally wrong.
"I know," the chief replied.
"Then why are we doing it?" asked the President.
The chief looked hard at him and said: "Because you won".
Scripts for that series were written in collaboration with former White House staff of the Clinton Administration. They knew what they would have done.
Put yourself in the position of a good person elected to power. You would discover, I think, that some of the things you previously thought you should do, or not do, and some of the things you imagined you would do, or not do, are suddenly no longer a matter of opinion.
With the power entrusted to you it would no longer seem right to indulge your own moral or philosophical inclinations. The national interest would have a clarity it had never had for you before, no matter how certain you had been.
This would apply I think to all important decisions, not just matters of life and death. New Zealand Prime Ministers would be aware of it in economic policy and in their response to Maori aspirations.
It will be the reason Helen Clark never reversed the economic reforms and why John Key hasn't acted on his party's pre-election plank to abolish the Maori seats. It is the reason he is Prime Minister and Don Brash is not. Deep down, voters sense whether someone is mentally equipped for responsibility.
When Senator Barack Obama was the Democratic Party's presidential candidate he firmly believed he should, and would, stop detention without trial of suspected terrorists at Guantanamo Bay in Cuba. He hasn't.
I don't know whether candidate Obama was ever directly asked what he would do if he was in a position to decide whether to take Osama bin Laden dead or alive, but if he was wise he would have fudged his answer.
So, for that matter, would the Republican candidate.
But as President, watching his soldiers move into Osama's compound, Obama would have known capture was not an option. The rest of us have the luxury of a moral and philosophical discussion about it. He had to make it final and tidy, no civil rights, no due process, no hostage to fortune.
I was surprised he called it justice. The only evidence is videotaped threats and claims that sounded like admissions.
If Osama wasn't the mastermind of 9/11 he made himself the figurehead for it. He wanted to be guilty and he probably was. Give America vengeance.
I was surprised, too at the picture from the situation room. In The West Wing they always sat around a table in suits to watch a covert operation come in on the satellite. Obama's crew could have been watching a football game - or election results.
The celebrations in America this week, reminiscent of a war's end, suggest we might turn a corner now, put the first decade of the 21st century behind us and get "terrorism" back into perspective.
It is not a war and never was - terrorism is a crime. It can cross national borders and requires an international response but it remains a crime.
Osama should never have been built into a spectral figure with a global network and untold stateless power. He was a lout who got lucky once.
In photos he was reminiscent of western radicals of the late 1960s. Long hair, beard, a glint in the eye that seemed more amused than malevolent. He and his comrades had comfortable childhoods, family wealth, ample education and the conceit to believe their convictions justified vandalism and violence.
To win a large following Osama needed to create an alien threat. He tried provoking the United States with bombs in embassies, then a warship, but America was just bewildered not enraged. So he aimed at its heart, its twin hearts, New York and Washington.
Give him credit, it was inspired. Domestic air travel was unguarded, airliners were ready-made missiles for anyone with a death wish. Bush took his bait and invaded an Arab nation that had nothing to do with it.
Muslims were outraged but they didn't rise to Osama's banner. Their uprising in Egypt and elsewhere this year is for leaders who know their limits.
Osama meanwhile had built himself a prison. There, inside high walls, windowless rooms and sealed chambers, without phone lines or the internet, he must have waited every day for the end he understood.