This sharp worldview divide helps explain the current dynamics in Washington around impeachment—why people are so angry, and why each side automatically counts each new revelation as evidence for its case. “When people hate the other side so much, they’ll resist just about anything, any kind of information, that would be beneficial to that other side,” Hetherington told me. Americans’ “partisan bias is so strong that even in the absence of strong counterarguments on behalf of the president, we’re seeing no movement in public opinion about impeachment.”
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The depth of America’s polarization is what makes this impeachment inquiry so different from the ones faced by Richard Nixon in the 1970s and Bill Clinton in the 1990s. Especially 45 years ago, partisanship “was not anchored in these fundamental, psychological worldviews,” Weiler told me. The two parties had not yet turned politics into a series of moral litmus tests on abortion, LGBTQ rights, and other highly charged issues. Policy debates were just that: debates, with space for respect and compromise. By the Clinton years, this dynamic had started to shift at the elite level, but members of the two political parties had not yet fully sorted themselves by fundamental differences in worldview, Hetherington said. “It’s the marriage of worldview and partisanship that creates this toxicity to politics,” he told me. “It’s a volatile marriage, to say the least.”
Not everyone in America fits neatly into these camps—fixed versus fluid, conservative versus liberal, Republican versus Democrat. The country is full of people with mixed identities and beliefs who occupy some point in the middle of the political spectrum. But their lives are still influenced by the people who listen to talk radio, read partisan websites, and watch MSNBC or Fox News. Hetherington and Weiler compared people with intensely partisan identities to smokers: Their exhalations shape the environment of the people around them, even those who aren’t smokers themselves.
This effect makes it harder for people in the gray space of politics to weigh evidence for themselves and make up their own mind, a process that is especially important on a high-stakes issue like impeachment. It’s impossible to know what lies on the other side of this inquiry—how Trump will react as new evidence emerges, how a trial in the Senate will play out, how it all will affect the 2020 election. But one outcome seems sure: This bitter fight will make it even harder for Americans to see their political opponents as reasonable humans. Instead, impeachment may end up serving as one more guidepost, pointing Republicans and Democrats to their respective sides.