John Quiggin, writing at both his eponymous blog and Crooked Timber, makes a very valid point:

the real political news of the last six months is the fact that the US now has a standard two-party system, arguably for the first time in its history. From Reconstruction until the final success of Nixon’s Southern strategy in the late 20th century, the fact that the Democratic Party represented the white establishment in the South made such a thing impossible. Under the primary system the two “parties” were little more than state-sanctioned institutional structures to ensure that voters (outside the South) got a choice of exactly two candidates.

He then discusses some of the recent trends in US parties, noting the push-back by more ideological activists against efforts by the Democratic Leadership Council and others to keep the Democratic party a catch-all party (though John does not use that term):

The netroots phenomenon is one reaction to this. But even more striking is the fact that the Democrats in Congress now match the kind of party discipline shown by the Republicans. After the 2006 elections, most commentary assumed that the party could not possibly hold together with its slender majorities in both houses, but they have clearly learned the basic dictum of party politics “We must all hang together, or assuredly we shall all hang separately.”

Then John makes a comparative point:

The degree of partisanship in the US, until recently far less than in other democracies, is now greater than in many. [This is in the CT version, and is phrased a bit differently in the other blog.]

My comment (at Crooked Timber) was:

In context, it seems it refers to voting in the legislature. Is there evidence that cross-party voting is becoming more common in the legislatures of other older democracies at the same time it is becoming less common in the US House (and even Senate).

And John’s response was:

I’m referring to a range of things, including the improved performance of third parties and independents in a number of English-speaking countries (Australia, NZ, UK) for example, and (more subjectively) a tendency towards convergence in the political positions of major parties.

It looks as if comments are now closed at CT, but I was hoping to keep the conversation going, so might as well do so here. It is certainly true that third-party voting is on the rise in the countries mentioned in John’s response. In NZ they now have proportional representation, so that is hardly a surprise. (And, of course, Australia has had PR in its Senate for a long time.) Nonetheless, third-party voting had increased in NZ even before the change in the electoral system. And indeed, third-party voting is up in the UK, even with no change in the (national) electoral system.

But the bigger point is that the way I understood the point about partisanship in John’s post (which I may well have misunderstood), it was referring to increase in party discipline, the ideological content of party platforms, the distinctiveness of the two main parties, and other indicators that the parties, per se, are more important for structuring political debate and conflict. This is really a separate question from the number of parties. In fact, these are two separate dimensions–intraparty and interparty–though they may be related systematically.

There has always been higher third-party voting in the other English-speaking democracies using first past the post (or, in the Australian lower house, the alternative vote) than in the US. One way to understand this difference that has always made the most sense to me is that there was less demand for third parties in the US because the two parties themselves were so flexible that they can accommodate views that would find expression in separate parties elsewhere. British institutions–parliamentarism, specifically–demand greater party unity, which in turn generated more demand for separate parties to express viewpoints that can’t be accommodated in the bigger parties.

So, the question for the US party system would be whether greater consistency and distinctiveness of party positions–and discipline in legislative voting–will increase demands for new parties. Well, maybe it already has. It is not widely appreciated is that third-party/independent voting is up in the US, too. It looks trivial compared to these other countries, but since 1990 it has generally been at around 5% while having been consistently under 3% range previously. (I do not know the 2006 numbers, but I suspect they will be low, because third-party voting is driven so much by protest votes, and in 2006, Democrats would have received most of these, as Republicans did in 1994–temporarily.) Still very low, from a cross-national perspective, and perhaps not indicative of much of anything. But still a change. And perhaps it will rise further, if we have indeed entered an era when we finally really do have a “standard two-party system, arguably for the first time in its history.”

Finally, regarding John’s point about “convergence of the major parties” in other English-speaking countries. I agree that this has happened in the UK and that the increase in third-party voting is partly a response to that. I suspect that even with “converging” UK parties and the “diverging” US parties, on most issues the two US parties remain closer to one another than do the two main UK parties. More to the point, it is worth noting that polarization of the leading parties can also produce a rise of third parties–the Social Democrats in the UK in the 1980s being a case in point. Third parties can arise in either the center or the “extremes” or on entirely new dimensions. The key distinction between the US and the other democracies we are discussing here is the extent to which the issues that might give rise to third parties can be instead represented within an existing party. In the US, the answer has almost always been that they can be, through capturing a primary election in some districts where the new issue–or a more extreme position on an existing issue–is salient. That’s a matter of the intraparty dimension, and if the US parties are becoming more cohesive, there could be increasing pressures for some issues to gain expression through third parties.