If you are looking for someone to blame for the polarized nature of our politics today, here are two nominees: Franklin Roosevelt and the political-science establishment.
Together, they set out the argument for the situation we have in Washington -- a Republican Party loaded with conservatives, a Democratic party larded with liberals, and few in between. The results have been gridlock, rancor, and a sense of despair if not hopelessness in the capital and across the country.
We have a political landscape where it is possible to argue that the most conservative Democrats in Congress today are more liberal than the most liberal Republicans.
There is virtually no overlap, no real party dissenters of the sort who were unacceptable to FDR, who wanted a party of ideological purity, and who were inexplicable to political scientists, who looked longingly at the ideologically disciplined parties in Europe and wondered why American parties so defied logic.
But with FDR and the political-science establishment having had their way, the United States has its biggest political crisis in modern history.
Party caucuses always have reinforced party discipline, but for the first time both caucuses are enforcing ideological discipline as well.
In the course of their work, lawmakers almost never encounter views that depart from their own or form friendships with their political adversaries. If they don't practice ideological compromise inside their own parties, they are less likely -- less able -- to practice it on the floor of either house of Congress.
"We finally got ideological purity, and it's a disaster for the country," says former Gov. Angus King of Maine, an independent. "We have ideological gridlock. You can't solve problems this way."
Indeed, the lack of a middle in the American political class is the American problem. The irony is that the American problem repeatedly has been held up as the American solution.
The most prominent advocate for ideologically aligned parties was Roosevelt, who once told Sam Rosenman, the first White House counsel: "We ought to have two real parties -- one liberal and the other conservative."
FDR set out to create just that with his effort to purge conservatives and New Deal foes from the Democratic Party. He singled out, among others, Walter George of Georgia, Ellison Smith of South Carolina, and Millard Tydings of Maryland, all of whom prevailed against the onslaught of White House opprobrium.
For whatever reason, the mushy party system prevailed -- and had unforeseen consequences even for Roosevelt. Many of the most ardent opponents of the New Deal turned out to be the most ardent supporters of the president's initiatives in foreign affairs, supporting Roosevelt on Lend-Lease, so much so that party alignment was doomed as World War II approached.
It gained new life a dozen years later, however, when the American Political Science Review published a landmark article called "Toward a More Responsible Two-Party System." The essay argued that American parties needed "sufficient internal cohesion" and a "degree of unity within the parties" that they lacked at mid-century.
"However one may deplore that system, he must concede that it has displayed, if nothing else, a very impressive ability to survive," Austin Ranney, then a political scientist at the University of Illinois and later the chairman of the political science department at the University of California at Berkeley, wrote in a contemporary critique of the 1950 report.
One reason the old system survived for so long is that the multiplicity of interests and ideologies inside American parties imposed the sorts of restraints on the majority that Americans liked, much like the checks and balances and separation of powers designed in the Constitution to protect the rights and viewpoints of the minority.
Now we have just the kind of political-party system Roosevelt and the political scientists envisioned. We are living the future, and it does not work.
"When the political scientists were thinking about these things in the 1950s, they were focusing on the good things the 'more responsible' party system might bring," says Larry Bartels, the co-director of Vanderbilt University's Center for the Study of Democratic Institutions. "Now that we're living it, we see a lot of the bad consequences. Now political scientists are wringing their hands about the negative implications of polarization."
A recent National Journal study showed that every Republican member of the Senate has a voting record to the right of every Democratic member of the Senate. Only five House Republicans have a voting record to the left of Rep. Gene Taylor of Mississippi, the Democrat with the most conservative voting record. The journal has been conducting these studies since 1982. Only once before, in 1999, did the Senate have a profile like it does today.
If you vote for a Republican today, you are very likely voting for a conservative, and if you vote for a Democrat you are very likely voting for a liberal. That's clear.
One other thing also is clear: The political system is a lot worse off.
David Shribman is executive editor of the Pittsburgh Post-Gazette.
Contact him at: firstname.lastname@example.org