There are two schools of thought concerning Joe Biden, Vice-President of the United States.

One, the dominant view, says that he's an idiot. This, they say, is the politician who shoots off his mouth without pausing to worry about the safety catch.

Another school holds that Mr Biden is nobody's fool. The talk show comics can make their jokes, but this is a Beltway veteran who knows how to get things done. If his President happens to be dithering over an important issue in an election year, Mr Biden is perfectly capable of a rambling "gaffe" on national TV just to nudge his commander-in-chief.

He did it just last weekend. While Barack Obama was being pressed to say what he believed about gay marriage, Mr Biden turned up on NBC's Meet The Press. "I am absolutely comfortable with the fact that men marrying men, women marrying women and men and women marrying are entitled to the same exact rights, all the civil rights, all the civil liberties," he said.

Mr Obama, who had rejected equal marriage in 2004 because (so he declared) of his religious beliefs, seemed to fall into line. Suddenly, his opinion had ceased to "evolve". He too told the cameras that same-sex relationships should enjoy marriage rights.

Even while Mr Biden was apologising to Mr Obama for talking out of turn, it became clear that the Veep's error was no accident. The President's campaign team had already swung into action to force Mitt Romney and the Republicans to confront the issue. Interestingly, conservatives were not keen. Even as North Carolina was joining 30 other states in banning gay marriage – against six in favour – the right went into hiding.

In Britain, meanwhile, all of David Cameron's socially-liberal rhetoric on equal rights in marriage found no expression in the Queen's Speech. His LibDem partners made no fuss over that. At Holyrood, First Minister Alex Salmond was reiterating his personal view – churches wishing to solemnise gay unions should be free to do so – while deferring to the outcome of still another consultation.

On both sides of the Atlantic, this is supposed to be an explosive issue, one liable to cause politicians to tread warily. Faith groups, overwhelmingly, would have it no other way: for most, this is a matter of profound importance. Some Muslims among them have claimed that civilisation itself is at stake. Dull reality, like popular opinion, is more complicated.

For one thing, it doesn't matter what Mr Obama thinks about gay marriage, nor is his view the political equivalent of opinions held by Mr Salmond or Mr Cameron. Short of an executive order – and that won't happen – the President will leave this argument to the states. In Britain, meanwhile, the argument over equity – over pensions, property, or hospital visiting rights – was settled, for those in need of justice, by the Civil Partnership Act (2004). The rest is symbolic.

In the US, a host of rights for gay couples depend still on legal recognition for their marriages. Mr Obama has come off the fence, however, mostly because his re-election team have made a strategic choice. They can count the number of states voting against same-sex unions, but they can also estimate the number of young people liable to support the President in this fight. Mr Obama wants that youth vote.

Neither he nor his re-election will alter reality for gay partnerships in North Carolina. That isn't even half the point. Why was Mr Romney ducking the question this week? Why were his supporters declaring that the President's statement was a distraction from the pressing issue of the economy? Tradition surely demanded that a Republican candidate would offer something incendiary for the sake of the evangelical "base". Instead, conservatives took a different view: on this one, they could lose.

Opinion polls in Britain tell the same story, time and again. Despite decades of effort by elements in the tabloid press, homophobia is in decline. The passage of the 2004 Act certainly left the majority supremely unfussed. Very few were ready to deny equal rights of inheritance or life insurance recognition to people who wanted to make a legal commitment. For most, it was no big deal. The sole remaining contestable word, here as in the US, is marriage.

Given the views of most faith groups – or their leaders, at least – I have never understood why a gay person would want recognition from organised religion.

If I'm baffled, that probably counts as my problem. On the other hand, it strikes me as odd that robed types who worry endlessly over the condition of marriage would turn away anyone seeking the full church/temple/mosque experience. That's their problem.

"Love the sinner," runs one formula, "but abhor the sin." This strikes me as high-end sophistry, missing – as sophists do – any human dimension. It amounts to a brutal thinning of the flock, too, however you do the counting. Yet the furore among the religious over the possibility that the word "marriage" might be allowed to the non-straight is peculiar. As an argument, it makes no sense.

Nobody – not Mr Obama, not Mr Salmond, not Mr Cameron – has dared to suggest any religious group should be forced to conduct marriages. That's the essence of our First Minister's "personal view": if a denomination wishes to solemnise unions, it should be allowed to do so. Otherwise, it's their choice. Where is the threat in that? Where is the risk to God or civilisation?

People who are gay, lesbian or otherwise patterned catch a glimpse of pink triangles. History says you couldn't blame them. In Britain, their contest over legal existence – as lawyers would say – is over. All that remains is an argument at once deeper and more simple: can they be people, too? Some truly ramshackle theology has been called upon simply to avert the possibility. The business of having the right to blow money on a church wedding has been turned into a test of humanity.

The religious will regret that, I think, once the wiser heads among them begin to remember all the doctrines of universal love.

In the US, the issues are immediate, practical and akin, increasingly, to the old struggle for civil rights. Many hundreds of common entitlements are at stake. Were Mr Obama the Lincoln of the hour – I'm not holding my breath – he would recognise as much.

In Scotland, we wait to see whether the First Minister is susceptible to one big donor and to churches that no longer – their big con – command many votes. In England, we wait to see whether Mr Cameron still yields to the witless shires. On both sides of the Border, politicians fail to grasp what Mr Obama's re-election team have noticed: gay people also have a lot of votes.

Some people like a church wedding, no matter what. Some might even like it better after it has been grudged. Personally, I've never gone in for that sort of thing. Their God and I do not occupy the same universe, mercifully.

If Scotland is to be "a beacon", however, as the First Minister likes to say of his hopes, then insisting on equal rights to a basic Co-op nuptials might be a good place to start.