So, then, David Miliband – political colossus, or inconsequential footnote? The greatest loss to British politics since the fall of Margaret Thatcher, or a failed leadership wannabe who will soon be forgotten?
There were plenty of opinions flying around this week in the wake of the South Shields MP’s shock decision to quit Parliament for a well-paid but scarcely high profile role running an international rescue charity in New York.
Predictably, it was his old mentors Tony Blair and Peter Mandelson who led the grief-fest, both expressing the hope that this would be but a temporary exile from which their protege would one day return in triumph.
Many Blairite cheerleaders in the media viewed Mr Miliband as so significant a figure that the ‘project’ would not survive his departure, though in truth it has been no more than a twitching corpse since his 2010 leadership election defeat.
The Conservative commentator Peter Oborne, writing in the Telegraph, took a rather different view of his career, however.
“Any detached judge has always been able to see that David Miliband was not front rank. He is a hopeless public speaker and has never once expressed an original thought,” he wrote.
Oborne contrasted Mr Miliband’s “cosmic sulk” after losing the Labour leadership to his brother Ed with Denis Healey’s loyal service under Michael Foot after a similarly unexpected setback in 1980.
The difference between them, he argued, was hinterland: Healey, who fought with distinction in the Second World War, knew that losing the leadership was a trivial matter by comparison, whereas Miliband, who has spent his entire adult life in politics, had no such perspective.
My own view for what it’s worth is that David Miliband was not a complete politician, but nevertheless still the best on offer at the time Labour was choosing a successor to Gordon Brown in 2010.
Oborne is right to point out that he certainly wasn’t in the front rank as an orator, but this didn’t prevent John Major reaching Number Ten and staying there for nearly seven years.
Where he was more lacking was in his tactical acumen – as was seen in his various hamfisted attempts to set out a distinctive New Labour policy agenda during the Gordon Brown years.
If these were covert leadership bids, they were spectacularly unsuccessful ones. If they weren’t, he should have taken much more care to ensure they were not interpreted as such.
In his favour, he was certainly one of the brainiest people operating in public life over the past decade or so and also, it has to be said, one of the nicest.
As regular readers of this column will know, I was never a huge fan of New Labour, but with David it never spilled over into personal acrimony in the way it occasionally did with some of his North East Labour colleagues.
But it was not so much his cleverness or niceness that made him the best candidate to lead the party in 2010, it was simply that he was the party’s most popular and well-known figure among the wider public.
It may seem obvious that a party wanting to return to power at the earliest opportunity should take note of what the public thinks when choosing a leader, but actually they seldom do, as both Mr Healey and later Ken Clarke also found to their cost.
In the end, it is this very popularity that has forced Mr Miliband to the point where he now feels Labour’s chances of winning the next election would be better if he were 3,000 miles away from Westminster.
It was this, coupled with the peculiar dynamics of Labour’s electoral college which showed he was also the most popular choice of Labour activists and MPs, which would always prompt those comparisons with his brother’s performance.
Has he taken the right decision? For himself, for his brother, and for the Labour Party, almost certainly yes.
But that still doesn’t alter the fact that the Labour Party made the wrong one when it decided to pass him over.