I interviewed Joe Biden once, you know. The Vice President is coming to see David Cameron today and their conversation might be relevant to one of the puzzles of British politics: what is the Prime Minister's foreign policy?
All that most people know about Biden is that he is a bumbler who talks too much, but I drove from Washington to Wilmington to speak to him in 1995 because, as a member of the Senate Foreign Relations Committee, he advocated American intervention in Bosnia.
I was in the US to report for the BBC on the pressure on John Major to do something about Serb aggression.
As it happened, the pressure was not that great. Paddy Ashdown had been on his high liberal horse for a while, demanding that Britain should use force if necessary to stand up to "ethnic cleansing", then a phrase still unfamiliar in English.
But Major was under little pressure from his Nato allies, naturally wary of entanglement. In particular, Bill Clinton thought that, if the Europeans were so bothered by the siege of Sarajevo, they could bomb Serb supply lines themselves.
In early 1995, Biden was the leading voice in the Senate urging US military action – even John McCain did not support the use of US force until after the Srebrenica massacre in July. So off we went to Wilmington, in Biden's state of Delaware, to hear the case for a new doctrine in world affairs that had been forming since the end of the cold war in 1989.
It wasn't called "liberal interventionism" then, but it has been the most important idea in US and British foreign policy ever since.
At the time, David Cameron was a public relations person for Carlton TV. His views on foreign policy were unformed, but he was a Thatcherite, and Margaret Thatcher also advocated intervention in Bosnia.
So maybe that was where he started. And he was impressed by Tony Blair. Less than two years after becoming an MP in 2001, he voted for military action against Saddam Hussein.
When he became Prime Minister, Cameron's priority abroad was to extricate British forces from Blair's interventions. The pull-out of combat troops from Iraq was completed in May 2011. Next, Cameron set a deadline for withdrawing from Afghanistan.
The first big moment in Cameron's foreign policy came in early 2011. He led a trade mission to the Gulf, at his most Majorite, a pragmatic, business-minded Tory.
He even gave a speech to the Kuwaiti parliament in which he declared: "I am not a naive neocon who thinks you can drop democracy out of an aeroplane at 40,000 feet."
But he was forced to stop over in Egypt en route, as the Arab spring was under way and Mubarak had just been overthrown. Within days, as the Libyan insurgency threatened Gaddafi, Cameron suddenly became the kind of neocon who thought you could, after all, drop democracy out of an aeroplane.
The big difference was that liberal interventionism had lost its innocence in Iraq. What was surprising, though, was the zeal with which Cameron took it up. And it was unexpected that he should seek the advice of Blair himself.
Hence the two risks that Cameron has taken this year. First, he has given British support to the French intervention against al-Qaida-inspired forces in Mali. He could have said that we were a bit busy in Afghanistan, but he seems to have become convinced that Britain should play its part.
Second, he has used astonishingly Blairite language, of the kind he might once have described as that of "a naive neocon", to connect Mali with the hostage-taking in Algeria and the struggle in Libya.
"We are in the midst of a generational struggle against an ideology which is an extreme distortion of the Islamic faith," he told the Commons. On the same day, as the Spectator editor Fraser Nelson pointed out, President Obama said in his second inaugural address that "a decade of war is now ending".
Perhaps, when Joe Biden is in Downing Street, Cameron could ask him to have a word with the boss and decide whether the leaders of the free world are coming or going.