In the shadow of 1860 - America's "two nations" go to the polls
"No two nations on earth," wrote the Ohio Senator Benjamin Wade, "entertain more bitter feelings of rancour toward each other than these two nations of the Republic."
The two nations in question were the southern and northern peoples of America in the run up to the Civil War.
The historian Allan Nevins believed it was this "sectional consciousness, with all its emotional and psychological implications" which made war inevitable by 1861, not the issue of slavery per se.
Long before they were defined by grey and blue on the battlefield Americans had split into two sociologically and culturally distinct societies, sealed off from each other by distance, economics and a localised media.
Today the shadow of this division looms, barely acknowledged, over America's mid-term Congressional election, which has descended into a rancorous culture war with blasts of literal bellicosity at the edges.
Though you would not want to push the direct parallel with the 1850s too far, in this key quality - the emergence of exclusive "separate" consciousness - it is relevant.
In Angola, Indiana, I saw two thousand people assembled in a college gymnasium to hear the Fox News commentator Glenn Beck. Beck himself spoke moderately: America's problems began in 1915 with attempts by "progressives" to regulate business; the best solution to any problem is private, not public. He did not, as previously, call President Barack Obama a racist. He urged his followers to love their enemies.
But the speakers that surrounded Beck were on a different script. Merchandise stalls sold the Gadsden Flag - a coiled rattlesnake with the slogan "Don't Tread on Me" - symbolising the promise of armed resistance during the American Revolution.
A local tub-thumper during the warm-up attempted to claim not only that the battles of Bunker Hill (1775), Fredericksburg (a Confederate victory in 1862), Iwo Jima, Khe Sanh, Fallujah and Helmand had equivalently "defined America" - but that the very latest battle in this conflict was being fought right now on American soil.
The Tea Party movement never invokes the American Civil War but revels in the imagery of the War of Independence. It maintains a discreet social silence on a figure like Jefferson Davis but idealises George Washington.
In this ideological scheme it is the Constitution of 1787 that has been "destroyed" by President Obama's healthcare reforms, and by the $787bn fiscal stimulus.
When Republican Congressional candidates describe the current "ideological battle" as a battle to "defend the flag on our own soil" the question arises: who is the battle with, and what form will it take?
The Tea Party movement is sociologically, not just overwhelmingly white but devoutly Christian, and often - but not exclusively - rural. Its adoption of placard imagery open to the charge of racism, and its initial craze for historical costumes, blindsided the liberal media in the USA into believing the movement was fake, or "Astroturf".
Its capture of key nominations in the Republican Congressional primaries proved its support extended far beyond this core activist group.
The Tea Party is now dictating policy and candidate selection to parts of the Republican Party, forcing mainstream Republican politicians to make a straight choice: do a deal with the Sarah Palins and Glenn Becks to get them off your back, or confront them in defence of a conservatism that is fiscally orthodox but socially tolerant. Few have openly chosen the latter.
As a result, the Tea Party movement gets to define American conservatism anew - and its definitions are exclusive: everything statist is deemed ungodly, unconstitutional; everything socially progressive spits on the graves of the heroes of Iwo Jima; every taxpayer handout to the undeserving poor defiles the flag.
If the key to American politics before 1861 was a split into two demographically separate "nations" then the parallels today are uncomfortable.
Then the South was defined by a white, slave-owning elite leading a mass of white farmers who saw Lincoln's attack on slavery as just one part of industrial capitalism's attack on their way of life.
They too believed they were defending the Constitution - not just over states' rights. J Mills Thornton, who studied the political ties between the "yeomen" of Alabama and the plantocracy discovered that, for the former, their entire conception of individual freedom and equality under the law had become bound up with the defence of slavery.
The North, in turn, represented not just a new economic model: it contained a different people. By 1861 its population included freed slaves, southern whites alienated from Dixie culture and millions of European migrants - including tens of thousands of Germans so steeped in the traditions of 1848 that they would march, uncomprehended by their English-speaking generals, onto the battlefields from Shiloh to Chattanooga singing socialist anthems.
America's two nations today are "virtual" - distributed across state borders by information networks, divided by the unseen boundaries that segregate many American towns and cities along lines of colour, lifestyle and class. But they are no less easy to identify. It feels to me like they are primarily defined by their attitude to the state and its role in the economy.
A city like Gary, Indiana, blighted by industrial decline, is now 84% black. The neighbouring steelworks, America's biggest, is mixed and has a significant number of white workers: yet streets and the steelworks are part of a shared political culture that is pro-Democrat, liberal and multi-ethnic. It is a culture that accepts the state as having a role to play in economic life, that does not see any wider moral or constitutional issues raised by America's attempts to create a healthcare safety net. The anger here is that Obama and the state has not done enough.
A city like Elkhart - a vehicle manufacturing centre 100km to the east - can feel like part of a different nation. The unemployed autoworkers I met there in 2009 expressed the desire for the state simply to "get out of our way".
One, Ed Neufeldt, had introduced President Obama to the rally that launched the fiscal stimulus there, back in February 2009. The image of Obama embracing Ed was flashed across America - symbolising the new President's cross-over powers into this part of middle America. When I met him in April 2009 Mr Neufeldt was still prepared to give the President tacit support.
Eighteen months later he has become a celebrated figure in the local Tea Party movement, receiving a name-check and a standing ovation at the Glenn Beck rally:
"I guess I've switched sides," he told me.
He was disappointed with the outcome of the stimulus and bank bailouts but that was not the clincher: "I guess what did it was the President's position on abortion".
To America's newly militant "nations" of the right and left, every political controversy impacts - as Nevins understood about the 1850s - "emotionally and psychologically".
Ben Clement, a black community leader in Gary told me:
"When you hear the vitriol on the TV - it's culture based, it's race based and it's frightening. Your stomach tightens into a knot: you think if they think that about the President - what are they going to think about me?"
In the Glenn Beck rally both Beck himself and many in the audience are reduced at times to tears. He tells them:
"The progressives had to destroy our faith. They did it with something most people don't even know about. In our churches - all of our churches - there are termites, some of them are wolves. They've been eating for so long that our churches are nothing anymore. But you must get this out: you must know what social justice and collective salvation and all of this nonsense is all about, and where it came from. It was put into our churches to destroy us."
Some of America's mainstream media is in a state of denial and disorientation over the Tea Party movement, as are some political strategists in Washington. Though the Republicans since the 1970s explicitly based their election strategy on courting religious conservatism in the south, it was always assumed that this visceral plebeian tendency would remain a minority strand in the GOP, controllable by the elite.
At first much of the media, staffed at senior level by the children of the Lyndon B. Johnson era, looked at the Tea Party and saw "just" the same old anti-abortion groups that had plagued Reagan and Bush Senior.
Meanwhile pro-Democrats revelled in the electoral calculation that a right-wing dominated Republican Party would hand the struggling President an unexpectedly clear victory in 2012.
In all cases the commentators under-estimated the Tea Party's momentum. What has changed is that its ideas have become defining ideas, as they have tapped into a seam of frustration and despair among the victims of the recession.
Driven by the movement, states such as Arizona have already picked tentative battles with the Federal authorities over tougher immigration laws. Should they win office on 2 November 2010, the Tea Party candidates will champion a new "states sovereignty" bill, aimed at weakening the power of the Federal state.
It is hard to see where this stops - short of some cathartic showdown with Federal authority or some miraculous turnaround in the economy.
Even then, there is no direct read-off between hardship and the rhetoric of resistance.
Observing the way both black and white communities have responded to the new penury of the middle class - by hunkering down with family, church and community - provides a clue to why "identity" on both sides of the argument has become so important.
Of course these are only parallels - we are not about to see history repeated. And I am certainly not predicting civil war.
Most Americans still do not count themselves part of any other "nation" than the USA.
For now the battle takes place within the Republican party, just as it took place within the south in the 1850s between what Nevins described as "two southern ideas".
The first conceived the conflict with the liberal North in terms of conventional politics and saw it as containable within the existing institutions; the second acknowledged the emergence of a Southern nation that would transcend party politics and Federal law. The latter triumphed.
Mainstream Republicans are having to do their thinking fast in response to the Tea Party. Mitch Daniels, Indiana's governor and tipped as a Republican candidate in the race for the White House in 2012, tells me:
"People ask me, is this a civil war? I say no - it's growing pains. A little creative hell-raising on behalf of freedom is not a bad thing... Now, when the confetti's fallen and quite appropriate alarms have been raised, I think at some stage it will be necessary to stand in front of those people and say - you were right about the diagnosis, here are the sorts of things we'll have to do if America is going to get back on its feet - and that's a transition that is yet to happen, but I hope and believe it will."
That is Plan A for the Republican establishment: to corral the anger of the Tea Party behind a new politics of fiscal austerity in 2012, designed and led by the Washington-based elite. To make, once in Presidential office, a compromise with Democrat governed states over issues like abortion or migration.
It may work. But co-existence is hard to achieve once the genie of "sectional consciousness" is out of the bottle.
When I met Civil War historians staging a re-enactment of the 1860 election debate in full costume on a handcart near the battlefield museum at Chickamauga in north Georgia, surrounded by American tourists in their baseball caps and shorts, they were all too aware of the parallels.
Park ranger Christopher Young, sweating under his top hat, broke out of character and told the crowd:
"The debate you've just heard was prelude to massive warfare. So be aware that the words we use can be far more lethal than any weapon on the battlefield."
Watch my report from Georgia on Newsnight at 2230 on Wednesday 13 October 2010. Or catch it afterwards on the BBC iPlayer.