We have not seen the intensity of political conflict and the radical separation between the two major political parties that characterizes our age since the late 19th century. Within Congress, the parties have become purer and purer distillations of themselves. The parties are now more internally unified, and more sharply differentiated from each other, than anytime over the last 100 years. Moreover, this polarization is not limited to those in office. Over the last generation, there has been a dramatic ideological and partisan sorting of voters as well. A center in America’s governance institutions has all but disappeared. . . .
[T]he major cause of the extreme polarization of our era is the historical transformation of American democracy and America's political parties set into motion by the 1965 Voting Rights Act. Thus, perhaps the extreme polarization over the last generation should not be seen as aberrational (indeed, the pre-1965 structure of parties is the one to view as aberrational). This polarization, for better or worse, might be the "mature" structure of American democracy. As such, it is likely to be enduring, despite the best efforts of Presidents and reformers to transcend the extreme polarization of recent years.
I am not convinced of Pildes' prognosis. Yes, the process of realignment has run its course. Yes, the one party rule of the American South by Democrats from the end of Reconstruction to 1965 was aberrational. Yes, the political process in the United States "naturally" favors a two party system in which the parties are ideologically distinct. But, the two party system is out of balance right now.
Ideological Gaps Are Great Because The Relative Strengths of the Two Parties Is Out Of Balance
Partisan preferences in the United States aren't anywhere near 50-50 among people with a preference. The current Republican party has shrunk to its strongly conservative core in the wake of a 2008 election that was a repudiation of George W. Bush's administration, and it has been captured by an even more conservative subset of the GOP because the party establishment was discredited by the party's electoral defeats.
Democratic party identification is up, but because its establishment was not discredited, its basic ideological bent has not changed very much. The soft support it has received from moderates has increased Democratic party power without expanding the ranks of those actively involved in serving as elected officials and running the party very much. It is broader in support and has a bigger cushion in electoral office, mostly because it has captured a large share of moderates alienated by GOP extremism for the moment. Recent Gallup polling provides some fairly direct evidence that GOP extremism alienates moderate voters.
But, while an American style electoral system "naturally" produces a two party system, its natural tendency is to produce nearly evenly split parties. It takes a crisis like the Great Depression or the social revolution of the 1960s, to throw the balance of power between the two parties far out of balance.
In other words, the deep ideological divide between the two major political parties at the moment is largely a result of the Republican party becoming much more conservative, and that extremism isn't stable.
We can see the instability in the 2010 election cycle. While both parties are having some primary battles, the intensity of the conflict is much greater for the Republicans who threw out Utah's incumbent Senator, for example, because he was not conservative enough, despite the fact that he is one of the most conservative Senators in the nation. The Tea Party movement in the GOP has pushed an already conservative political party further to the right.
Former Tom Tancredo has gone so far off the deep end that he is willing to run as an candidate of the American Constitutional Party which is off in John Bircher territory. When even conservative insurgent candidates, like Ken Buck, are calling the Tea Party activists "dumbasses," it is clear that conservatives, whatever they have accomplished, have overreached, and that the ideological pendulum in the Republican party is about to swing back towards moderation.
As the Republican party moderates its ideology, and the Democratic party holds its ideology largely steady, the result will be that the parties will be less far apart ideologically.
Ideology isn't static
Even though our electoral system tends to produce two political parties that are ideologically distinct, the issues that draw that line are not static. The Republican and Democratic parties almost completely reversed their respective ideologies over the past hundred years, with the Republican party going from being the liberal leaning party to the conservative one, and the Democratic party going from being the conservative party to the liberal leaning party. There is no reason to believe that the ideologies of the two parties will not remain fluid.
In the long run, ideological battles are won or lost, and conceded. No one in politics favors the de jure segregation that was the norm when realignment began. The political stances Strom Thurmond took on race at the end of his career would have been considered quite liberal when his career began. Conservatives lost that battle, just as the lost the battle to preserve slavery.
No one in politics favors dismantling Social Security, Medicare, Medicaid, or a predominantly public funding model for K-12 education. There are reforms to those programs on the table, but the basic notion of mandatory government support for those programs is secure. The Lochner/Hoover era effort to restrict the scope of government failed. Likewise, even the financial industry has no interest in return to the pre-New Deal state of affairs when securities were regulated under state rather than federal law.
The Left changed too. The Democratic party is not trying to mobilize rent strikes, or calling for the nationalization of the oil industry to appropriate its excess profits, or even calling for top marginal income tax rates of 70%. The American Left has pretty much given up the call for universal, free higher education that is the norm in Europe, for the time being. A single payer health care system didn't even make it to a floor vote in Congress during the debate on health care reform.
On some social issues like gay rights, young conservatives are far to the left of their elders and likely to remain that way, shifting the political center on the issue. Assuming that war does not come to dominate the national consciousness and the economy turns around, the political climate will change. Radical conservatives in the Republican party will lose ground to more mainstream candidates who have wider appeal. Bitter extremism doesn't sell well in ordinary times.
Right and left in politics are relative terms, not absolute ones. They are tendencies, not policy agendas in and of themselves.
So, while I believe that a clean partisan divide between two political parties will remain, as Pildes predicts, a long standing feature of the American political scene that is resistant to reform, I don't think that the parties will always be so far apart ideologically. And, when the Republican party is less extreme, moderates will stop looking like Democratic partisans, and compromise will be possible.