"By his friends shall ye know him." Politicians, and that includes Presidents, are never judged in isolation. Who has their ear? Who do they trust? Who are their political soul-mates?
When I worked for Tony Blair, Bill Clinton used to love to have regular meetings with centre-left leaders from Europe and elsewhere. We'd have long sessions - sometimes painfully long - going into every detail of public policy. The 'Third Way', as it was called, gave them all a sense of being part of a global redefinition of what it meant to be a non-Conservative, for want of a better phrase. Whether it cut much ice with the voters is another matter.
But today there is no equivalent to give President Obama any kind of support. For a start the left just isn't in power in very many places. Here in Britain the opposition Labour party is struggling to find a voice and is perceived by many to be too closely tied to the trade unions. Social Democrats, the nearest we have to the Democratic Party, although frankly even Obama Democrats are way to the right of us over here, are out of contention in big countries they once governed like Germany, Spain and Sweden.
The one place where they have a good chance of winning, France, is more of a headache than a help to Obama. The Socialist candidate, Francois Hollande, has been well ahead in the polls for a long time. But he's standing on a program that is so anti-business and so dependent on tax and spend that even other social democrats in Europe look away in horror. President Sarkozy has been very unsubtly hinting - let's face it, he doesn't do subtle - that Obama wants him to win and he may be right.
I think I've commented before that the Obama lustre still shines more brightly here in Europe than it seems to in the States. But if Barak Obama wanted to show he was part of an international movement for change, with allies in governments across the world, as Bill Clinton liked to do, then he's out of luck and out of friends.
Maybe he doesn't care. But he does need to convince a lot of people that it's the centre left that has the answers to the world's big problems, especially now he almost certainly faces a relatively moderate Republican opponent. And on that, I'm afraid, he's on his own.
This is Lance Price for CBS News in London.