Barack Obama, we are told, chose Joe Biden to be his running mate because he needed an older man, more experienced in foreign policy, to reassure American voters that the United States will be safe under an Obama presidency.
It's assumed that Obama also chose Biden because Biden's views on foreign policy are not radically different from his own. Since American foreign policy still affects almost everybody in the world, that makes Biden's views very interesting.
Joe Biden, now 65, has been a senator since he was 29. For almost half that time, he's been a member of the powerful Senate Foreign Relations Committee, which he now heads. He has been around long enough to leave plenty of evidence about his views and his reflexes, and it is safe to say that he qualifies as a liberal interventionist - or, as they say on the other side of the Atlantic, a liberal imperialist.
Unlike the neo-conservatives, who are brothers under the skin to the liberal interventionists, Biden does not believe that every problem in the world can be solved by the application of U.S. military power, but he does think many of them can be.
He backed the U.S. military intervention in Bosnia, the bombing of Serbia during the Kosovo crisis, the invasion of Afghanistan after 9/11 and the invasion of Iraq (although he subsequently had the grace to admit he was wrong and apologize for that).
Indeed, the Democratic vice-presidential candidate has even called for the use of U.S. troops in Sudan, unilaterally if necessary. He would doubtless agree with Obama's famous remark (over Iraq) that he was not against all wars, just against dumb ones.
But Biden's criteria for which wars are dumb wars are not very discriminating. A unilateral U.S. military intervention in Sudan would make the Iraq fiasco look like a wise act of statesmanship.
Biden has usually been a voice of moderation among the chorus of Democratic hawks vying to outdo their Republican colleagues in their hostility toward Russia and their enthusiasm for the "war on terror."
He did support the expansion of NATO right up to Russia's frontiers (and visited Georgia immediately after the recent fighting), but he has resisted the temptation to paint Russia as the Soviet Union in sheep's clothing. And his contempt for the "war on terror" has been consistent and exemplary.
"Terror is a tactic," Biden has said. "Terror is not a philosophy."
It is a mantra that everybody in U.S. politics should be required to chant each morning before work, even if it is slightly inaccurate. ("Terror" is actually an emotion. "Terrorism," however, is a tactic, a political tool or technique, more precisely, that can be used in support of a wide variety of causes. It is as misleading to declare war on terrorism as it would be to declare war on propaganda.)
When he briefly supported the invasion of Iraq, he did not do so out of an ignorant belief that Saddam Hussein had links with those terrorists. It was his liberal interventionism that drove this decision, combined with a naive belief that U.S. intelligence would not bend the evidence to serve the president's purposes.
So that is Joe Biden's take on foreign policy, and it probably isn't vastly different from Barack Obama's.
The difference lies mostly in the "experience" factor, which tells you all you need to know about the value of experience in these matters.
It is Biden's long residence at the heart of the Washington political/military/intelligence machine that makes him such a conventional character.
All that stuff about Obama being "not ready to lead" is simply a coded warning that he might not lead in the time-honoured, conventional way. John McCain certainly would, and so would Hillary Clinton if she had won the Democratic nomination.
The selection of Joe Biden as his running mate is intended to allay those fears by linking Obama to someone who is deeply embedded in the conventional wisdom, but doesn't actually prove that Obama is, too.
There is still room for the suspicion that Barack Obama harbours a secret desire to move American foreign policy away from the traditional great-power realpolitik and the occasional forays into liberal interventionism. That would probably appall Biden and horrify the rest of the Washington establishment. Vice-presidents don't have a veto, so the choice of Biden poses no problem there.
But the Washington establishment probably does have a veto, so whatever Obama intends, Biden will not be disappointed by the outcome.
Gwynne Dyer is a London-based independent journalist whose articles are published in 45 countries.