Pressure has been building on president Obama to attend the UN climate talks in December. Arguably that is unfair, since the meeting was always intended to be at only a ministerial level.
But on Monday the heat was turned up by Gordon Brown, Britain’s prime minister, when he addressed the Major Economies Forum meeting in London.
Mr Brown said he would definitely go to Copenhagen, and urged other leaders to do the same.
That created a slightly awkward situation for Todd Stern, the US climate representative who was at the London talks.
The Forum is intended to provide a “more intimate” framework for discussion of the fight against climate change, among just 17 leading economies, including China, India and Brazil, instead of the 192 countries involved in the UN talks.
Ed Miliband, Britain’s climate change and energy minister, said that by the end of the meeting, he thought a Copenhagen deal was “more do-able today than it was yesterday.”
He promised, too, that the countries represented at the meeting would “strain every sinew” to get a deal at Copenhagen.
The most dramatic intervention, however, came from Mr Brown, who warned about the threat of climate “catstrophe”. His message was, in essence, “we have 50 days to save the world”.
His call for world leaders to go to Copenhagen to help deliver a deal, and his promise to go himself, were something of an embarrassment for president Obama, who has conspicuously failed to make the same commitment.
Asked about the president’s attitude, Mr Stern equivocated.
“We are not writing anything off,” he said, “but we are treating this as a ministerial meeting in the first instance.”
So would the president go?
“If the kind of progress is made that would warrant the presence of leaders, we would consider that,” he said. “I am not ruling out, in the right circumstances, some attendance by the president.”
In other words, if everything goes well, and it is clear that a historic climate agreement can be reached, president Obama will be prepared to turn up to share in the glory. If the meeting looks like being a horrible mess, ending up in acrimony and recrimination, we should expect the president to keep several thousand miles between him and the smell of failure.
It would be understandable if president Obama was reluctant to go to Copenhagen. He has been only recently - protestors hung up a big banner reading “right place, wrong time” – and that visit was one of his most conspicuous failures.