Is political polarization worse than it's been in the past?

Polarization is debatable — I'll pull the evidence on whether it's worse than in the past.

Is political polarization worse than in the past? The answer is: Yes, compared to the recent past - especially the mid-20th century - but with important historical nuance.

1. Yes - polarization is at a modern high

Most measures show polarization has increased sharply since the 1970s-1990s and is now at its highest level in decades.

In Congress / among political elites:

> Following a period of a much more balanced Congress during the middle of the 20th century, ideological distance between the parties began to grow during the 1970s to the extent that Congress is now more polarized than at any time since the late 1870s Reconstruction Era.

Researchers measure this using NOMINATE scores — which measure legislators' liberal-conservative positions based on roll call voting records.

One way to see it is the "overlap interval" — how many Republicans lie to the right of the most right-leaning Democrat and vice versa:

> Today, the overlap interval is zero.
> In the 1960s, for instance, you had intervals where about 50 percent of the legislators in the two parties overlapped.

A wide-ranging analysis of Congressional floor speeches found that political polarization has "exploded" over the past 20 years, and is now "far greater today than at any point in the past."

In the U.S., political polarization, in terms of ideological distance between Republicans and Democrats, has been growing significantly in recent years, so that it is now less likely to find a liberal Republican or a conservative Democrat than it was many years ago

Among the public:

The Pew Research Center has tracked this for decades:

The rise is even more dramatic for affective polarization — how negatively partisans feel about the other party, rather than just disagreeing on issues:

> In 1994 , only 17% of Republicans and 16% of Democrats reported very unfavorable views of the opposing party. By 2016 , those numbers had risen to 58% of Republicans and 55% of Democrats .

Other long-running data shows:

> Affective polarization in the United States, defined as masslevel hostility across partisan lines, has sharply intensified since the 1970s. For instance, [...] the proportion of Americans who state that they would be displeased if their child married someone from the other party has increased from about 5% in the 1960s to nearly 50% by 2010.

> The discrepancy between the in and out party thermometer scores steadily increased from around 25 degrees in 1978 to around 45 in 2020.

> Almost all the increase in affective polarization has occurred because of increased out-party animus.

The U.S. has also polarized faster than peer democracies. In a multinational study, in the U.S., affective polarization has increased more dramatically since the late 1970s than in the eight other countries they examined—the U.K., Canada, Australia, New Zealand, Germany, Switzerland, Norway and Sweden.

2. But not worse than ever in American history

When viewed over 200 years, today's level is not an unprecedented anomaly:

> Some political scientists have pointed out that — viewed within the context of data from the last two centuries — today's levels of polarization are not such an alarming anomaly compared to those occurring during the time of slavery and similar points along the historical continuum.

At the elite level, data shows:

> Because the NOMINATE data generated by James Lo and his co-authors shows that partisan elites in the U.S. are as polarized today as they were around the time of the Civil War, it suggests that there is a huge gulf in the middle that's not being responded to by the two parties

A similar finding is reported as: the NOMINATE data generated by James Lo and his co-authors shows that partisan elites in the U.S. are as polarized today as they were around the time of the Civil War

Some historians argue that:

> Clearly the country has been more polarized than it is today. What's unusual now is that the political system is more polarized than the country.

That distinction between elite polarization and mass polarization is important:

> In the real world, ideological and affective polarization are certainly more evident among party elites than ordinary partisans

In other words: members of Congress and highly engaged activists have sorted into two very ideologically consistent and mutually hostile camps with almost no overlap, while the average voter is less ideologically consistent — though increasingly dislikes the other side and sorts by identity.

Bottom line