Conservatives are angry. They are angry about President Obama, about taxes, and about government spending. If it were legal, Tea Party conservatives would like to vaporize much of Blue America.

Liberals are not angry—they are disgusted. They are disgusted by the endless questions about President Obama’s birth, by the hysteria over “death panels,” over Republican candidates demanding an end to masturbation. If it were legal, liberals would move all of red America behind a large screen where its antics would be less embarrassing.

If the dominant tone of conservatives is shrill, the dominant tone of liberals is saracastic. The philosophical position of Rush Limbaugh and Glenn Beck, expressed in body language, would be a raised fist and a clenched jaw. The philosophical position of Stephen Colbert and Bill Maher would be a raised eyebrow and a wrinkled nose. Angry coverage on Fox News has become the standard bearer of the right. Irony and mockery on Comedy Central have become the standard bearer of the left.

Right-wing blogs reek of blood and guns, violence and revolution. The tree of liberty, they remind us, needs to be refreshed with the blood of patriots. Look at the weapons of the left—Colbert’s sly smile, Maher’s snigger, and the endless jokes about the stupidity of George W. Bush, Sarah Palin, and Christine O’Donnell. Even the bumper stickers of the right are grave in tone. They ask, “What Would Jesus Do?” Their opponents’ bumper stickers respond, “What Would Scooby Doo?”

The right is convinced that the left is evil. The left is convinced that the right is retarded.

In the conspiracy theories propounded by the right, Barack Obama is not an idiot but a clever double agent whose purpose is to destroy capitalism, Christianity, and America from within. If you listen to the left, Glenn Beck and Sarah Palin are small children who have gotten their hands on very large bazookas and need to be told to put down the weapons—preferably using words with few syllables.

Both anger and contempt have deep psychological roots. Anger usually stems from feelings of unfairness or betrayal. Contempt is anger mixed with disgust. Anger and contempt are not just emotions. They are scripts that determine our political conversation. If you are a conservative blogger, you will hunt out material that shows liberals to be unpatriotic and dangerous, because your audience wants affirmation of its underlying feelings. If you are liberal, you will play up material that shows conservatives to be stupid, because your audience wants affirmation of its sense of superiority.

This selective weeding does not always happen consciously. Just as interpersonal relationships have unconscious scripts that determine how people talk and argue, so, too, our national conversation follows scripts that are more powerful because they are unconscious. When we treat one another badly because we mean to behave badly, we know we are doing something wrong. When scripts inside our hidden brains make us treat others badly, we do not realize we are behaving badly. Couples in distress who come to marriage counselors are invariably blind to how their internal scripts are helping to produce the problems that mark their daily lives. If conservative America and liberal America were married to one another, this relationship would have one side wearing overalls, swilling beer, and screaming all the time, while the other sipped cappuccinos, read The New Yorker, and pretended it couldn’t hear a word.

If marriage research were a guide to politics, we could say that the scripts of the right and the left do us all harm—and that the left may be doing more harm to the relationship than the right.

In recent decades, the field of marriage research has been changed by a paradigm known as the Four Horsemen of the Apocalypse. Invented by marriage researcher John Gottman, the paradigm suggests that dysfunctional relationships often have four markers—criticism, contempt, defensiveness, and stonewalling.

Criticism is anger expressed. Broken pots and pans, and abusive relationships, often follow. But Gottman and others have found that while contempt may seem more dignified than anger, it is the single best predictor of an impending divorce. Of all the horsemen, it is the worst. Human beings, it turns out, will live with black eyes and bruises sooner than they will live with disrespect and disgust. Telling someone, “You piss me off,” is not as bad as telling them, “You repulse me.”

Couples in marriage therapy invariably have loads of evidence to justify their feelings. If you could haul liberal and conservative America into a counselor’s office, the left would produce loads of evidence showing that conservatism is regularly anti-intellectual when it comes to questions of evolution or global climate change. Sarah Palin really did evince a limited knowledge of foreign affairs during the 2008 election. George W. Bush really did say “misunderestimate.” Conservatives would tell the counselor about how liberals are always slow to see threats to national security, always “blaming America” and always quick to support international institutions such as the U.N. and the International Court of Justice.

What couples learn in counseling is that their conflicting visions are accurate, but accurate in the way caricatures are accurate. They miss nuance and fail to see how different underlying dreams prompt each side to value things differently. Surely underlying personality and different upbringing have much to do with the desire among so many liberals to see a president who is, first and foremost, smart, and the desire among so many conservatives to have a president who is, first and foremost, a patriot?

I’ll be the first to admit that marriage is not an ideal analogy for politics. Liberal and conservative America don’t need to love each other for the country to work. They just have to get along. And it is not as if the complex emotions that liberals and conservatives feel can be simplistically divided into one-side-is-always-angry and the-other-side-is-always-contemptuous. Liberals are often angry, and conservatives are regularly contemptuous. But as liberals and conservatives bring their warring marches to Washington this fall—demanding, alternately, a return to honor and a return to sanity—it is quite clear that the marriage research does have something useful to tell us about our unconscious scripts.

How can a country function when each partner constantly wants to show the other the light—and the door?

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