Compared to the tense security discussions US President Barack Obama has just concluded in the Middle East, the American leader's engagements in Britain today are more of a pleasure than a chore.
He has lunch with Britain's Queen Elizabeth II to celebrate her 90th birthday, meetings with Prime Minister David Cameron and dinner with Prince William and his photogenic wife Kate.
Still, Mr Obama's visit to the country that likes to regard itself as America's closest ally is controversial, for the US President will have to wade into the heated domestic debate on whether Britain should vote to leave the European Union.
As the son of an African who allegedly suffered persecution by the British colonial authorities during the 1950s, President Obama was suspected of harbouring anti-British sentiments from the moment he came into office.
Mr Obama's decision to remove a bust of British wartime leader Winston Churchill from the Oval Office in the White House was also pounced upon by critics as evidence of his anti-British instincts. And the US President's occasionally unfortunate choice of gifts for British leaders - he once presented a British prime minister with a set of US movie DVDs and a plastic model of a helicopter - did not help either.
Much of this criticism was off the mark, although Britain's relationship with the US did cool for a variety of practical rather than personal reasons. Participation in the US-led invasion of Iraq in 2003 is now regarded by most British politicians as one of their gravest recent strategic mistakes; the much-awaited report of a lengthy official inquiry into that war is scheduled to be released this year, and it won't make pleasant reading in London or Washington.
And the financial crisis that struck Europe reduced London's ability to deploy troops in other conflicts, thereby diminishing Britain's significance for the US.
Prime Minister David Cameron claims to have addressed these difficulties. He responded to President Obama's appeals to boost defence spending by pledging to devote at least 2 per cent of Britain's gross domestic product to the military until the end of this decade, the biggest financial commitment of this kind in Europe.
And the Americans have reciprocated, by offering public support to Mr Cameron in the British leader's efforts to persuade his public to vote for the country's continued membership in the European Union in a referendum to be held on June 23. Mr Obama has repeatedly said that by staying in the European Union, Britain "gave Washington greater confidence in the trans-Atlantic alliance and helped make the world safer and more prosperous".
Mr Obama is aware that he must step gingerly into Britain's EU dispute. "He'll make very clear that this is a matter that the British people themselves will decide when they head to the polls in June," said Mr Ben Rhodes, the President's deputy national security adviser, referring to today's talks.
Politicians who want Britain to get out of the EU are already crying foul. A letter signed by 100 MPs led by Mr Liam Fox, a former defence minister, reminds Mr Obama that "it has long been the established practice not to interfere in the domestic political affairs of our allies".
Meanwhile, London mayor Boris Johnson has accused Mr Obama of "exorbitant hypocrisy" in arguing that Britain should limit its sovereignty by remaining part of the EU, while the US itself would never accept limitations on American sovereignty.
Mr Obama hopes to take the sting out of the controversy by engaging in a town hall-style discussion with young Britons tomorrow in London.
The assumption among American diplomats is that this meeting will highlight positive future opportunities in the US-Britain relationship, rather than dwell on the past.
Still, there is no question that Mr Obama's visit has highlighted lingering American worries about Britain's continued relevance, as well as British concerns about the commitment of the US to its "special alliance" with Britain.
Addressing such concerns will be a priority for the next US president.