It was brilliant while it lasted. Since he joined US President George W. Bush for a press conference on the lawn at Camp David a month ago, British Prime Minister Gordon Brown has managed to have the best of both worlds, convincing the US that he's a true believer in the "special relationship" between the two states and reminding Britons he's no Tony Blair. But the game may soon be up.
At their first summit, the workmanlike rapport between Brown and Bush perfectly suited both sides. The Bush-Blair love match was a thing of the past; that went without saying. The new duet would be a partnership, businesslike and profitable.
Brown looked at Bush and said he was pleased "to be able to affirm and to celebrate the historic partnership of shared purpose between our two countries."
Bush looked at Brown and said: "The relationship between Great Britain and America is our most important bilateral relationship."
Celebrants on both sides of the aisle recognized this as a marriage of convenience, but a successful one none the less.
In Britain, the headline writers were persuaded that Brown was "no poodle."
In the US, it was clear that Bush and Brown, like Bush and Blair before them, would "stay the course."
However, it is only a matter of time before their differences threaten to bring them down. Brown could soon be forced to make decisions about the deployment of British troops in Iraq that will put both his political resilience at home and his alliance with Bush to the test.
In the middle of next month, the top two US officials in Iraq, US General David Petraeus and US Ambassador Ryan Crocker, will report their findings on progress there. They seem likely to conclude that the US troop "surge" is working and the Iraqi government isn't.
I won't hazard a guess as to what Petraeus and Crocker will or will not have to say about the British presence in southern Iraq and about the security situation there.
But regardless of whether they talk about it, the fact is that the picture in and around Basra is far from pretty. By almost any measure, conditions in the south have deteriorated in recent years, both for Iraqi civilians and British troops.
In the aftermath of the Petraeus-Crocker report, everyone's attention will be drawn to Baghdad and its environs -- and to the US' predicament.
But at some point, heads will turn toward Brown and a single question will float his way: Now what are you going to do?
When that happens, the nature of Brown's administration could change radically.
Last week, Bush, in his speech arguing that to "abandon" Iraq would replicate the "tragedy of Vietnam," described himself with grim pride as a "wartime president."
The last thing Brown wants to be is a wartime prime minister.
For at least a year now, an assumption has lodged itself firmly in the British body politic: We're on the way out of Iraq; our boys and girls are coming home.
Though Blair never got credit for it (or blame from the US side) he presided over a massive drawdown of personnel -- from 46,000 in the spring of 2003 to 8,500 in May 2005 to 5,500 before he left office.
There the number stands today. It is expected to fall again, to 5,000, in the autumn, when the UK turns the besieged Basra palace, once one of former Iraqi president Saddam Hussein's smaller residences, over to the Iraqis and then concentrates its forces at Basra airport.