It is beginning to seem strange not that the US political system is breaking down, but that a constitution so extremely complex, so loaded with checks and balances and possibilities of obstruction, can ever have worked in the first place — let alone provided the frame for one of the most successful economies and polities the world has ever seen.

And it did not always work. In the decade before 1861, it broke down into civil war over the issue of slavery — with the borders of the Confederacy largely following those of the hard-line Republican states opposing President Barack Obama today.

For most of the century and a half since, however, some mixture of Union victory in the Civil War, the steady growth of the US economy, and the discipline provided by the struggle against communism allowed rival factions of US political elites to manage the system.

Breakdown might have occurred over Franklin Delano Roosevelt’s New Deal — the extreme Republican opposition to FDR was just as ideological as that of the Tea Party to Obama today — but the depth of the economic crisis, and the consequent strength of Roosevelt’s majorities, were such that hard-line Republicans were overwhelmed, and moderates co-opted, for more than four decades.

Obama has a respectable mandate, though nothing remotely like FDR’s. In fact, the Democrats won a small majority of the democratic vote not only for the Presidency and the Senate, but the House of Representatives as well. Republicans have a majority of seats in the House due only to the drawing of district borders by state governments; yet this, together with the powers given to a Republicandominated Supreme Court, the power of a minority in the Senate to block legislation, and the colossal over-representation of conservative white states in the Senate, has allowed them to paralyse much of government in the US.

The Republicans in Congress have been willing to create this danger for their country because, in many states, an ultra-radical Tea Party minority, representing a conservative middle class maddened by a decline in its social, economic, cultural, and racial world that it cannot account for rationally, has seized control of the party at local level.

In a more straightforward democratic system, the white conservative middle class would be forced to compromise (or, in some parts of the world, resort to armed revolt) in the face of changing demographic realities. The US constitution not only allows them to conduct a ferocious and seemingly endless rearguard action, but in the process, to endanger the US and world economies.

Samuel Huntington put his finger on part of the reason for the peculiar nature of the US system when he wrote of the US (in his 1968 book Political Order in Changing Societies) as an essentially pre-modern polity, with a medieval system’s intense fragmentation of power:

“The principal elements of the English constitution were exported to the new world, took root there, and were given new life precisely at the time that they were being abandoned in the home country”, he noted. “They were essentially Tudor and hence significantly medieval in character ... The institutional framework established in 1787 has, in turn, changed remarkably little in 175 years.”

In fact, the only time a medieval king or US president is really free to make policy is in time of war — assuming that he can create enough public alarm and anger to get parliament to pay for it.

But of course, the US is not a medieval state with a tiny government and standing army. It is a modern state with a huge bureaucracy, enormous military, network of state institutions, and, most of all, immensely costly systems of social welfare and medical support which are now regarded as rights by those very conservative middle classes who refuse to provide the taxes to pay for them.

In this way, the US today perhaps resembles more closely France in the decades before the revolution of 1789. In terms of underlying resources, France was by far the strongest single country in Europe, the homeland of the international language of the era, with the largest economy, the largest population, and the most prestigious culture. It also had colossal geopolitical ambitions in Europe and beyond.

Yet the French state was incapable of harnessing these resources for national ends. Over the decades, the monarchy had bought support or reduced opposition on the part of regional nobles and merchants by exempting them from a great range of taxes in effect creating a giant system of subsidies for the French elites. These “rights” of the elites not to be taxed were in turn defended by the regional parlements, bodies representing the local elites which blocked fiscal reforms and increased taxes in the name of resistance to “royal tyranny”.

The result was to wreck the state’s ability to raise money, repeated fiscal crises, the growing economic and military eclipse of France by Britain, the loss of French America, and, eventually, the French Revolution. For by 1789 not only had the parliaments and the regional elites wrecked the financial basis of the French state, their incessant and hysterical propaganda about the wickedness, oppression, greed, and corruption of the royal government played a key part in destroying the legitimacy of the monarchy in the population. The regional elites thought that they would be able to lead the revolution that followed. Instead, they were among its first victims.

The US is nowhere near revolution. Still, it is impossible not to view developments there without foreboding. As far as I can see, the only thing that could overcome the resistance of radical conservatives in the Republican Party and allow a deep reform of the US system would be a combination of economic crisis and outside threat on the scale of the 1930s — hardly a medicine to be desired, and one that would bring catastrophic dangers for the US and the world.

If, on the other hand, the US system continues to stagger on from crisis to crisis, the result will be to undermine the prestige of the democratic ideal in the world — an ideal of which the US has always been the greatest exemplar and standard bearer. In the short run, this may strengthen authoritarian states like Russia and China. In the longer run, it will increase the likelihood that should these regimes eventually fall, they will be replaced not by liberal democracies but by new and perhaps worse systems of authoritarian nationalism and populism. Remembering how crucial the US has been to freedom in the world over the past century, I pray that none of this will be the case, but prayer is not enough. Something needs to be done, and done quite urgently.