In the 1980s he was a fierce opponent of Ronald Reagan's foreign policy that sought to face down Russian Communism. In 1984, he supported the proposal, popular on the left, for a nuclear freeze that would have left the US dangerously overmatched by the Soviet Union in nuclear capability and miles behind in conventional weaponry.

Having distinguished himself with this consistent capacity for error during the Cold War, he got the post-Cold War era off to a cracking start by being wrong on the biggest issue then, opposing the first Gulf War in 1991.

This, remember, was not some wild-eyed act of gun-toting US unilateralism. It was painstakingly negotiated through the UN Security Council and supported by all America's European allies and most Arab states (including Syria). But Biden, perhaps by dint of that already accumulating experience, knew better and warned against the dire consequences if the US and its allies moved to enforce international law and force Saddam Hussein out of Kuwait.

Not long after, some sort of dim bulb seems to have lit up in Biden's head and he changed tack. Perhaps realising that his über-dovishness was neither objectively defensible nor (even in his home state of Delaware) politically wise, he shifted.