White House race turns nasty as Mitt Romney brands Barack Obama a 'disgrace'

So much for a lofty battle of ideas. The arrival of economic "big thinker" Paul Ryan on the 2012 Republican ticket has instead triggered an avalanche of personal attacks and insults unusual even by the bare-knuckle standards of US presidential politics.

Yesterday brought no respite as challenger Mitt Romney went on national television to accuse Barack Obama of being ready to stoop to anything to hang on to the White House, and running a "demeaning" campaign built on "division and attack and hatred".

That broadside, on the CBS This Morning show, followed a tirade the previous evening at a rally in the key swing state of Ohio, in which Mr Romney told his rival to "take your campaign… back to Chicago". The President's sole strategy, he went on, was to "smash America apart and then cobble together 51 per cent of the pieces. If an American president wins that way, we all lose."

The cause of Mr Romney's uncharacteristic display of fury was a speech earlier in the day by Vice President Joe Biden, who told a largely black audience in Virginia, another battleground state, that the Romney-Ryan recipe of budget cuts and deregulation would "put y'all back in chains".

The Republican reaction was a mixture of righteous indignation and outrage: "Had Ryan said that, he would have been told to get off the ticket," one party strategist commented. "This is what an angry and desperate presidency looks like," Mr Romney declared, condemning "wild and reckless" accusations that "disgraced" the presidency.

The abuse continued as an Obama spokesman then called Mr Romney's criticism "unhinged" – drawing the schoolyard retort from the latter that the only "unhinged" campaign was the one being run by the President.

But the roughhouse Obama tactics are deliberate, and the anger of his opponents anything but synthetic. The rhetoric and TV ads from both sides have been at best misleading and often downright fallacious.

In terms of sheer nastiness however, Republicans have yet to come up with one to match a Democratic ad suggesting Mr Romney was directly to blame for the death of a woman deprived of health coverage when her husband lost his job at a steel mill taken over by Bain Capital, the private investment firm run by the Republican candidate.

But the criticism will not bother the Obama campaign one bit. The blistering attacks are part of its basic strategy – which Mr Ryan's arrival has only accentuated – of portraying its opponents as advocates of law- of-the-jungle economics, that help the rich minority at the expense of middle- and working-class Americans. Whether that overall strategy is working is unclear.

Some post-Ryan polls suggest that Mr Romney has drawn level in the national race, but in key states like Ohio, the President still seems to enjoy a narrow lead. Republicans can expect a further boost, albeit modest, from their convention starting in 10 days in Tampa, Florida.

For the time being though, Democrats will keep up their barrage, focussing especially on Mr Ryan, author of a tax-cutting, welfare-slashing budget passed in March by the Republican-controlled House of Representatives. There are some signs too that the tactics are hitting home.

Mr Romney once said the Ryan budget – which most controversially part-privatises Medicare, the popular federal health programme for the elderly – was "marvellous". This week however, anxious not to upset the large contingent of seniors in states like Florida and Ohio, he insisted the budget proposals he would sent to Congress if elected would be his own.

For now though, one thing is sure. The high-minded discussion about eliminating the deficit and America's future that was supposed to be unleashed by the advent of Mr Ryan has not come to pass.