United States presidential campaigns are free entertainment that America gives the world. Hundreds of millions of people across dozens of lands watch each improbable step and laugh, cry and cheer.
But it is more than just a reality TV show. It matters. Only 5 per cent of the world's population lives in the United States, but the outcome will affect 100 per cent of us. We don't get to vote, but we have a stake in the presidential election nonetheless.
We know that the choice of president will influence the likelihood of the US making war.
Australia has a keen interest in America's wars. We are the only country in the world that has fought alongside the Americans in every major war of the 20th and 21st centuries. When America goes to war, so, historically, do we.
When we choose to join an American war, it has real consequences for the entire venture.
Consider this thought. One of the wise old men of American foreign policy, Brent Scowcroft, the national security adviser to Gerald Ford and George Bush snr, believes that the US might not have gone ahead with the invasion of Iraq if not for the decisions of Britain and Australia to join in.
"I don't think the President would have done it absolutely alone," he told me. "He needed some cover, and you and the British gave it to him.
"If you and the Brits had said, 'Sorry, Mr President, we can't go along with you on that,' it wouldn't have happened."
Scowcroft, a former US Air Force general, 82, and head of a successful corporate advisory firm, the Scowcroft Group, in Washington, is one of the most respected voices in US foreign policy.
If Australia indeed has such power, it enlarges the Australian responsibility for its policy decisions. But Scowcroft also pointed out that Australia would have paid a price for defying a US request for help.
"If you had said no, it would have been a serious blow."
When I reminded him that he disagreed publicly with Bush's intention to invade Iraq in a much-remarked newspaper opinion article just before the invasion, he replied: "It was a serious blow to me - I'm still anathema to the President."
Did that cost him, though? "No. But I'm not a country." In other words, Australian decisions on American wars, whether we play to type and go along or whether we decide to stand aloof, have real consequences for ourselves, for the US and for the state of the world. We really need to pay attention.
But surely the disastrous misadventure in Iraq will deter future American commanders-in-chief from launching any new wars? Not at all. There are three points here.
First, America is a country that is comfortable with war. In the 230 years since the Declaration of Independence, the US has invaded other countries on more than 200 occasions, according to the Congressional Research Service. That is an average of one foreign incursion every 14 months in the nation's history.
Second, the end of the Cold War was supposed to mean a standing-down of the US military machine. The opposite has happened. The Pentagon's budget today, after adjusting for inflation, exceeds its Cold War average by one-eighth, though there is no longer any nation that could be called a peer competitor.
"The truth is that there no longer exists any meaningful context within which Americans might consider the question, 'How much is enough?' " writes Professor Andrew Bacevich, a historian at Boston University and former US Army colonel in his book The New American Militarism.
The total defence budget is bigger than that of all other nations combined.
"During the entire Cold War era, from 1945 through 1988, large-scale US military actions abroad totalled a scant six. Since the fall of the Berlin Wall, however, they have become almost annual events."
Bacevich calls it "the normalisation of war". He goes on: "Policymakers have increasingly come to see coercion as a sort of all-purpose tool."
He wrote this before his son was killed while on duty in Iraq. As the US President, George Bush, has said, the lesson of the 2001 terrorist attacks in the US is that "this country must go on the offence and stay on the offence".
The third point is that, while it did seem that the disaster in Iraq would deter America's political class from further military adventurism, the picture has changed.
The surge in Iraq has been successful in reducing and containing deaths. A senior fellow at the Council on Foreign Relations and a former Bush staff member, Michael Gerson, argued in yesterday's Washington Post that the turnaround in Iraq is "the largest political story of the year".
Three presidential candidates remain in serious contention. They are the two Democrats, Hillary Clinton and Barack Obama, and the Republican, John McCain.
One of these has consistently and stridently advocated the invasion and also the surge. That candidate is McCain, a hawk and a genuine American war hero. The recovery in Iraq helped propel him to take, in all but the formalities, the Republican nomination for the White House.
As Gerson wrote: "The issue that was supposed to dominate the campaign and destroy the Republicans has helped to elevate a strong Republican candidate."
Another of the candidates voted in support of the invasion, then later reversed course, and has struggled to explain this position since. That candidate is Clinton. Iraq, and her flip-flop on the subject, has plagued her campaign. She is neither hawk nor dove but opportunist.
Then there's Obama. From day one he opposed the invasion of Iraq. He goes further. He said last week: "I don't want to just end the war, but I want to end the mind-set that got us into war in the first place." One of his advisers, Susan Rice, later elaborated: "It's the mind-set that assumes that solutions to our problems are in the first instance military ones."
So one candidate is a hawk, another a dove, and the third is both and neither, flapping back and forth between the two flocks according to the political wind.
Obama would seek to restore war to its place as an instrument of last resort. McCain is a man much readier to resort to force, though he suffered dreadfully as a prisoner of the North Vietnamese and understands the human consequences of war better than almost anyone alive.
And Clinton? From what we have seen, she will follow whatever course of action is most strongly counselled by the opinion polls of the day.
Our likely involvement in any wars of the next four years is in their hands.
Peter Hartcher is the Herald's International Editor.
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