In this guest post, Jesse Callahan Bryant discusses research and findings of the recent article in Environmental Politics – Intraparty polarization on climate change in Republican Party discourse, 1987–2016
In 1991, U.S. Representative John Porter from the State of Illinois stood up on the House floor to defend spending on global environmental degradation. He pointed out that the rational, preventative investment in climate mitigation was what any fiscal conservative would call a good deal. It promised development opportunity and centring American leadership and business. He was a Republican.
So was Dana Rohrabacher of California, who spent the early 90s telling the House that global warming was a fabrication of multinational corporations and unelected foreigners, an elite scheme to strip sovereignty from the little guy.
In most histories of American climate politics, the period when climate change tore the American right in two directions is often forgotten. In the scholarly literature especially, the Republican Party often appears as a singular agent of denial, and the analytic question is how far it has pulled away from the Democrats and reality. That framing has produced a lot of good research. It also carries the assumption that a party can be treated as a single actor with a single position moving along a single line.
In my article in Environmental Politics, I do my best to tell a more detailed story of that evolution. Using 809,628 congressional speeches from 1981 to 2016, merged with ideological ideal-point estimates from the Database on Ideology, Money in Politics, and Elections, I split the Republican caucus into centre-right and far-right flanks and compare how each of them talked about climate change over thirty years.
What I found was that in many Congressional sessions, climate change was more discursively polarised within the Republican Party than it was between the parties, and more polarised within the GOP than guns, abortion, or immigration ever were.
To accomplish this, I train word embeddings on the congressional corpus and use embedding regression to estimate how far apart the semantic context of “climate change” and “global warming” sits across groups: Democrats versus Republicans, centre-left versus far-left, centre-right versus far-right. To put these measurements in context, I run the same analysis on guns, abortion, and immigration, plus a semantically inert control word.
Abortion is fiercely polarised between the parties, which surprises no one. But within each party, I find that abortion discourse barely rises above the control. Republicans talk about abortion in more or less the same way as other Republicans. The same holds for guns and immigration. For most of the past 30 years, climate change is the exception, and only on the right. As I mentioned above, between 1999 and 2014, centre-right and far-right Republicans diverged from each other on climate more than Republicans and Democrats diverged from each other.
Democrats went the other way. From 1997 onward, far-left and centre-left climate discourse steadily homogenised, converging below the control baseline by the 113th Congress on a shared frame.
My magnitude measures reflect that a fight occurred, but they don’t reveal what it was about. For that, I used a computational tool to identify the most prototypical usages of climate language by centre-right and far-right Representatives in each era, then read those speeches closely. Three phases of GOP climate polarisation emerge.
In the first phase, roughly 1987 to 1998, the centre-right talked about climate change as international stewardship. Porter’s speech I mentioned at the beginning of this post is the prototype. Climate spending was foreign policy, and Republicans were the responsible custodians of a neoliberal global order they had helped build. Meanwhile the far-right was already fully at denial, with Rohrabacher its clearest voice. There was no gradual radicalisation on that flank. In general, the far-right position arrived early and held for the rest of the study period.
In the second phase, 1999 to 2008, the centre-right dropped internationalism. In its place came small-government and national-security-tradeoff framings. Roscoe Bartlett of Maryland shows the manoeuvre plainly, telling colleagues that “you may or may not agree with whether our earth is warming or not,” but that anyone worried about getting too much oil from overseas “would want to do pretty much exactly the same things that those people who believe we have global warming want to do.” He was managing a divided audience, and he knew it. The far-right over the same years, while still focused on denial, became more specified around specific forms of disinformation and conspiracies about solar cycles, “global wobbling,” and termites as a massive source of carbon emissions.
The third phase, 2009 to 2016, is where the argument changes character and tends toward the common dynamics much of the scholarly literature invokes today. On the far-right, the target shifted from incorrect studies to bad scientists. Ted Poe of Texas said climate policy “takes control of Americans and their independence and makes us slaves to the federal government.” Rohrabacher called climate science “the biggest power grab in history,” handing elites “a seemingly legitimate reason” to control ordinary people.
The centre-right, for its part, kept conceding that climate change was real but relocated the problem. Brian Bilbray of California put it as cleanly as anyone: “This is not about climate change. This is about proposed regulations by a bureaucracy in a field of law that was never meant to address this issue at all.” What had been a question of international policy in 1991 was now a question of the overreach of unappointed bureaucrats.
Importantly, the gap between the centre and far-right narrowed across these thirty years. This pattern of divergence followed by convergence is the signature of what European scholars of the right call contamination, or the discursive polarisation mechanism by which the far-right stakes out ground, and the mainstream is eventually pulled toward it.
But the convergence did not happen the way contamination models usually describe. The centre-right did not really become denialist so much as the two factions arrived at a shared enemy: the administrative state. The centre-right got there through libertarian objections to regulatory cost and agency overreach. The far-right got there through generalised distrust of elite institutions and conspiracy. This hedges theories of far-right contamination to suggest that centrist politicians need not fully adopt every aspect of a political frame for contamination to be operative. Arriving at a shared enemy might be enough.
With these results in mind, we might consider that governmental context likely matters quite a lot. Schertzer and Taylor Woods (2025) find that nationalism is the dominant frame in U.S. presidential climate discourse. In the legislative branch, I find populism doing the convergence work instead. In Congress, both factions found an enemy in domestic Executive branch elites, not foreign others. While a president speaks as the symbolic embodiment of the nation, a legislator speaks, in theory, for those everyday citizens they’re meant to represent.
Then there is the puzzle of why climate was uniquely available for this. One explanation is that guns, immigration, and abortion were already lodged in settled cleavages (i.e., national identity for the first two and religious morality for the third) which left factions little room to contest their meaning. Climate change entered politics later, quickly, and originally as a technocratic question.
Of course, issues that begin as technocratic problems are all immediately exposed to populist and anti-elite attacks. But at the same time, climate change’s underdetermined entry into American politics created space to pull it in different directions. If that is right, issues that arrive as technical problems might pass through a period of intra-party sorting before they harden into partisan cleavages, which is a claim someone could test on other issues and other systems.
This study is, of course, descriptive. Convergence consistent with contamination is also consistent with compositional change in the caucus, or with both factions responding to the same external pressure. The Koch network and the Tea Party were both reshaping Republican climate politics over exactly this period, and embedding-based analysis cannot separate organisational coercion from organic discursive influence. Separating them would take a different design focused on lobbying money, caucus composition, and some exogenous shock. I ended the study at 2016 on purpose, to see the party before Trump restructured it. Whether the convergence I document completed itself after 2016, or whether new fractures opened, is the obvious next question. It is also, now, the more urgent one.
Bio
Jesse Callahan Bryant holds a PhD from the Yale School of the Environment and is currently a John Paul II Postdoctoral Fellow at the Pontifical Academy of Social Sciences in Rome. He studies the American far-right, environmental politics, and computational approaches to political discourse. His work has appeared in the Annual Review of Sociology, The Sociological Quarterly, Social Problems, and Socius.
