Regular readers now know that most of my texts encourage people to take the measure of the word us. It is an enormously powerful term, but the eternal question is whether it only becomes meaningful when it also implies its opposite. I don’t think so; I don’t believe us necessarily implies themand in my writing I challenge readers to take this moral possibility seriously. Among other things, I expose the ubiquity of us-versus-them thinking in everyday life, and trace its connection and contribution to so many things we (a close relative of ours) would like to be different.

There have been many calls for unity lately. Unit is just us in Sunday-meeting clothes, so I’m all for it. I was all for it before it was even a thing. But because I take the idea seriously, I also wonder what people mean when they call for unity. What does unity look like? Who should unite, and how do we know when it’s happened? Turns out these are harder questions than people think.

First, let’s ask what unity is supposed to do. What is it supposed to accomplish? Calls for unity always arise after a tragedy. Something bad has happened because we are not united, and if we unite, these things will stop happening or happen less often or something. The presumption here is that the young man who nearly blew the former president’s head off was radicalized or driven or inspired or somehow stirred to action (the mechanism is never really made clear) by our vicious cultural climate. If we “come together as a people,” 20-year-old men will no longer climb onto the roof of a building and try to shoot their way into history. That, at least, is the implicit claim.

As you can see, these are actually two claims: one is a claim about the past, the other is a prediction about the future. The first is that national division caused or at least meaningfully contributed to the attempt on Trump’s life; the second is that unity will prevent similar behavior in the future. Yet we have no idea whether either of these claims is true. Dozens of diligent journalists, along with untold numbers of law enforcement officials, have combed the available evidence for evidence of Crooks’ motivations, to no avail. They have pieced together a handful of seemingly contradictory life experiences that point in confusing directions, which may say nothing more than that he was young and still figuring out his place in the world. We do not know why he acted, and may never know.

And if the first claim is unknowable, the second is downright improbable. As David Wallace-Wells noted Recently, “(e)lf of the last twelve presidents have suffered an assassination attempt or a plot against their life.” John F. Kennedy was shot and killed. Ronald Reagan was shot. Two different would-be assassins tried to shoot Gerald Ford in one month. A man threw a real grenade on George W. Bush. As historians Matthew and Robert Dallek recently pointed out, at least one in four American presidents have been assassinated or nearly assassinated by assassins. At the time, no one thought that these attempts heralded a crisis of national division, but more importantly, history gives no reason to think that unity, whatever it may mean, will prevent another attempt in the future.

So much about what unity is supposed to accomplish. But maybe we should instead ask ourselves what unity looks like? What makes a country united? Normally when we talk about a united or unified group, we mean that we share a common goal or act with one mind. We say, “We are united in wanting to accomplish X; we are united in our desire for Y.” But what does that statement actually mean? I think most people would agree that it would be nice if we could magically achieve certain results. For example, I think it would be great if there were less gun violence, and I don’t think I’m being too far-fetched when I say that almost everyone would agree with me. In fact, I can think of a whole bunch of results that almost all of us would agree would be nice to achieve.

But so what? The question is whether we agree on how to achieve these outcomes. People like to say that the country was largely united behind President Bush after the 9/11 attacks, and it’s fair to say that we shared a common desire to end the threat of transnational terrorism. But that unity quickly collapsed as his policies took shape, notably the disastrous war in Iraq, torture in CIA prisons, and indefinite detention without trial at Guantanamo.

In other words, unity on ends is meaningless without unity on means. But in a complex society it is foolish to expect us to agree on means, and disagreement is not evidence of a crisis. Sure, everyone agrees that it would be nice if we had fewer shootings, but we clearly disagree on how to get to that happy state. And diversity on means is especially to be expected in a federal system. I don’t think Montana has to look like Maryland, and I don’t think the municipal code in Savannah, Georgia, has to be the same as the municipal code in Santa Monica, California.

There are limits, of course. The Constitution guarantees that each state shall maintain a “Republican form of government,” meaning that New Hampshire cannot appoint a king, and the Bill of Rights guarantees certain individual liberties that transcend state lines. The right to effective assistance of counsel in a criminal case, for example, means the same thing in South Carolina as it does in South Dakota. Likewise, the Commerce Clause and Congress’s power to tax and spend enable the federal government to achieve a degree of national uniformity. The federal Civil Rights Act of 1964, for example, which legally ended Jim Crow laws nationwide, was enforced under the Commerce Clause and the Affordable Care Act (Obamacare) enforced under the authority to levy taxes.

We should fight like hell about the reach of the Constitution, which is just another way we disagree about means. I might think that the Constitution should reach more of the national life than another person; I think the Court was wrong, for example, in Roe v. Wade. But I think most people would agree that there are large parts of the nation’s life that are completely untouched by the Constitution and should remain so. For example, Florida has no income tax. I think that’s bad policy, but who cares what I think? If I don’t like it, I don’t have to live in Florida. Or I can move to Florida and try to change it. In a federal system, people vote with their feet. That’s why Texas can’t ban women from leaving the state to get an abortion. Texas can’t ban women from going to California for an abortion any more than California can ban Elon Musk from moving his business to Texas. Federalism is both sword and shield.

In short, when it comes to resources, division in a democracy is not a defect, but a feature. In fact, I think the sharper the disagreement over policy choices between the major parties, the better. Sharp disagreement over policy gives voters a clear, easy-to-understand choice. Democracy is well served by clearly contrasting policy positions.

So, what is this, unity? In light of President Biden’s announcement that he will withdraw from the 2024 presidential race and endorse Vice President Kamala Harris, the question seems more urgent than ever. Unity will not do what it is supposed to do, and is, at least as widely understood, not a desirable outcome for our democracy. So why do I feel so strongly about it? That is the subject of my next essay.