The barbarism of the recent Tucson, Arizona murders reminds us of the crucial distinction in constitutional government between bullets and ballots. Barbarians know only the force of bullets, not the reason behind ballots. The rule of law that informs our constitutionalism requires common respect for reason—not that all will agree but that all, in principle, can exchange arguments and act with civility as a result of them.

Thus it was disturbing to see some politicians and pundits maintain that certain types and styles of arguments somehow fostered the barbaric attack. One congressman even maintained that we now need "to watch what we say," as it might set off a lunatic, as the murderer evidently was. Thus the barbarian, the person without reason, would set the standard for how civilized people are able to argue.

In effect this argument to end all arguments simply says: "Shut up!" Thus, a silencing act would lead us to barbarize ourselves by ending our ability to engage in the kind of robust exchange fitting for a free people. Barbarizing ourselves can come in two forms: a resort to bullets is the most obvious way but we also can become barbarians by destroying our vision and limiting our ability to think. This ability—with all of it concomitant risks—is essential to the debate that is required of constitutional government.

Unfortunately, the Arizona murders are not the only recent example of self-barbarization. This occurs among academics, as we see in the edition of the Adventures of Huckleberry Finn that turns all instances of "nigger" into "slave." In trying to avoid giving offense, the edition loses Twain’s depth and the instruction, especially about race.

We fully appreciate Huck’s growing awareness of Jim’s humanity only by knowing how savage his times were. To cite one quick example: When Aunt Sally asks Huck whether "anyone" had been killed in a steamboat accident, Huck answers "No ’m. Killed a nigger." Using "slave" here would distort the meaning of the conversation.

We can alter novels to produce happier results—in To Kill a Mockingbird a mixed-race jury could acquit Tom, as a Wall Street Journal reader protested; in The Call of the Wild Buck, the Nietzschean super-dog, could bite some Japanese tourists instead of killing Indians; or in Native Son Bigger Thomas could kill a black maid. But by compromising our artists’ greatest achievements we cut ourselves off from their instruction. We think we know better than they—the arrogance at the heart of stupidity and the reversion to barbarism.

The self-barbarization that has been afoot for decades may have influenced Congress’s recent preference for reading the Constitution in abridged rather than in its full form. However laudable the idea of beginning this session of Congress with a reading of the Constitution, the lackluster execution diminished the exercise. The Constitution creates no cakewalk government. It forces difficult choices for a self-governing people, as we strive to live under the law and not our whims. This is why the founders regarded the republican (small "r") form of government the one most demanding in moral and intellectual character. Did the founders not agonize over the compromises involving slavery? By glossing over the issue, did not the House fall short of the Founders’ boldness and their humility and their republican virtue?

Barbarism occurs not just when we are too violent but also when we are too mild or, to use the word properly, slavish. Barbarism today is most likely through silence. The failure to read the entire, original document was such a silence.

The greatest of the compromises within the Constitution is over slavery and the counting of "other persons" (understood to mean slaves) for purposes of representation—the oft-misunderstood 3/5 clause. Since the 13th Amendment abrogated this passage, the House members omitted its reading.

What defenders of the Constitution (not the least Frederick Douglass) emphasized was that the original Constitution does not mention the word "slavery." The Constitution actually points the way toward the means of its abolition in a unique clause that cannot be amended (Article V, along with the equal representation of states in the Senate). Even the so-called "fugitive slave clause" (far more odious than the 3/5 clause) does not actually affirm a right to slavery. The states could have abolished slavery on their own, just as they might have enabled women’s suffrage (which New Jersey did briefly).

The statesmanship of the founder of the Republican Party, Abraham Lincoln, halted the growth of the "barbarism" of slavery (his party actually used that term) and therefore threatened its future existence. He used constitutional means, such as an Emancipation Proclamation that freed slaves only in the Confederacy, as an exercise of his war-making authority. Total abolition would require the 13th Amendment.

By stigmatizing the sin of slavery (but not the slaveholder), Lincoln preserved the Union and the founding. In a speech in Columbus, Ohio Lincoln warned about those who would "blow out the moral lights around us" through their indifference and bring about the eternal darkness of barbarism. Our politicians and intellectuals today speak up for barbarism when they remain silent about our "better angels."

Ken Masugi is a Fellow of the Ashbrook Center and a professor in Ashland University’s Master of American History and Government program.