Last week, in City of El Cenizo v. Texas, a federal district court enjoined much of Texas’s new anti-“sanctuary city” law, SB 4, from taking effect. That bill stirred eerie echoes of the American past; I heard faint tones of Abraham Lincoln’s pro-slavery rival Stephen A. Douglas in the stated intent of its sponsor.

Start with SB 4. In its main features, it told Texas localities, universities, or officials—on pain of fines and even jail time—that they could not stop local peace officers from investigating the immigration status of those they detain and notifying federal authorities; forbade the same localities and officials to limit “the enforcement of immigration laws;” and instructed local peace officers to provide “enforcement assistance” to federal immigration authorities. In addition, localities would be required to obey “immigration detainer requests,” which are administrative requests from immigration authorities to keep individuals in jail even after charges have been dropped so they can decide whether to deport them.

Texas Governor Greg Abbott signed SB 4 in May, and proclaimed, “Texas has now banned sanctuary cities.”

On August 30—one day before SB 4 was to take effect—federal Judge Orlando Garcia of the Western District of Texas issued a preliminary injunction against most of the law. The detainer provision, he held, probably violates the Fourth Amendment’s bar on “unreasonable” arrest and detention. The “cooperation” clause, he held, almost certainly violates the federal immigration code, which, unlike SB 4, allows cooperation with local law enforcement only under strict conditions—including that all cooperation be under the direct authority of the attorney general, not local immigration officials.

But, in the most interesting part of the opinion, Garcia held that the ban on any “policy” that “prohibits or materially limits the enforcement of immigration laws” is so broadly written that it would bar local officials from even criticizing state immigration policy—and thus almost certainly violates the First Amendment.

That brings us to Douglas, Lincoln’s foe in the 1858 Lincoln-Douglas debates. Douglas emerged victorious in the Illinois Senate race against Lincoln, then lost to him in the presidential election two years later. The “Little Giant” (5’4”) stood beside the 6’4” Lincoln and held his foe’s stovepipe hat at the Inauguration. Three months later he died of typhoid fever.

In the antebellum years, Douglas tried to thread the needle between the Northern and Southern wings of the Democratic Party, but, as the dispute heated up, he moved closer to what anti-slavery forces called “the Slave Power.” After John Brown’s anti-slavery raid on Harper’s Ferry in 1859, Douglas made his “Sedition Law” speech on the Senate floor. Southern states, citing the danger of “servile insurrection,” had long banned any internal criticism of slavery. Now Douglas proposed making the ban national, through a federal statute that would “suppress all conspiracies and combinations in the several states with intent to invade a state, or molest or disturb its government, its peace, its citizens, its property, or its institutions.” In other words, to guarantee the safety of the slave states, Douglas proposed outlawing the anti-slavery movement—and the Republican Party.

“The Harper’s Ferry crime,” he told senators, “was the natural, logical, inevitable result of the doctrines and teachings of the Republican Party.” Lincoln, he said, had warned that a “house divided against itself cannot stand.” Republican Senator William H. Seward proclaimed the clash between slavery and free labor “an irrepressible conflict” that would leave the nation all free or all slave.

Republicans were preaching disunion, Douglas said. The solution was to stop their mouths through “indictments and convictions” that “will make such examples of the leaders of these conspiracies as will strike terror upon the hearts of the others, and then there will be the end of this crusade.”

Lincoln warned in his Cooper Union speech that “Senator Douglas’ new sedition law” would suppress “all declarations that slavery is wrong, whether made in politics, in presses, in pulpits, or in private,” but the bill never advanced.

The Sedition Bill controversy is a particularly inglorious chapter in Douglas’s checkered career; but in factual terms he was right. An institution like human slavery can, in the end, be maintained only if government silences not only slaves but free people. By designating some humans as less than human—as holders, in Chief Justice Roger B. Taney’s phrase, of “no rights which the white man was bound to respect”—American society authorized warfare against its own people, and the brutality of that internal war inevitably spurred a reaction. The slaves bore the brunt of the war; but with the passage of the Fugitive Slave Act of 1850, it spread to ensnare free states. The Supreme Court’s Dred Scott decision served notice that even the concept of a “free state” might soon be struck down. Controls on speech would be the logical next step.

America’s war on its own people could not be won unless all dissent, indeed all freedom, was eventually crushed.

This takes us back to Garcia’s opinion in City of El Cenizo. He pointed out that SB 4 forbids local governments or any officer or employee of a local government to “adopt, enforce, or endorse” a policy against cooperation with immigration authorities. Violators can be hauled into court by any citizen who disagrees with them. Courts finding a violation must assess fines of up to $25,000 a day against the locality—or the official. And any official violating the “endorsement” ban is to be removed from office by the court.

The bill’s sponsor, Texas Senator Charles Perry, explained during debate that “endorse” means “support, identify with, and it is, it becomes part of our DNA [sic], or culture to endorse that, that we believe enough in it to put our name on it.” If, for example, a sheriff or police chief were to write a newspaper article criticizing SB 4, he added, “it’s effectively creating a culture of contempt or noncompliance,” and would therefore run afoul of the law. As for free speech, “I don’t know that that’s a free speech issue if you’ve been elected to uphold the law. You don’t get the right as a free speech [sic] to go out and not uphold the law.”

Garcia found two kinds of fault with the “endorse” language. The first is that, if it means what Perry says it means, it is a “content-based restriction on speech.” In this case, it is what First Amendment lawyers call “viewpoint based”—as Garcia wrote, under SB 4 “one viewpoint on local immigration policy is banned and the opposite viewpoint is permitted.” That’s a big First Amendment no-no. But beyond that, the statute is unconstitutionally vague—“a person of ordinary intelligence has no guidance whatsoever as to what is prohibited,” he wrote. Vagueness is also a First Amendment red light, because it can intimidate speakers who want to engage in fully protected speech, and empower prosecutors to move unpredictably against those they dislike. In the case of SB 4, Garcia wrote, “Prosecution to remove a local official from office will end up being selective, arbitrary, discriminatory, and in violation of First Amendment rights.” But “under the American system, local elected officials, and persons who are appointed or employed by local governmental entities are expected to engage in open, robust debate on such issues, as such debates lead to a more informed electorate.”

Garcia quoted Abbott, for example, as saying that when the bill takes effect, “I’m putting the hammer down ... We are going to be asserting fines. We’re going to be seeking court orders that could lead to putting these people behind bars, the officials who are violating their oath of office.” Was he threatening to jail local officials—by coincidence Democrats—for maintaining forbidden policies, or simply for opposing the state’s policy? Beyond that, Garcia noted, the state of Texas had filed suit against Travis County—Austin is the county seat—for violating SB 4 even before the law took effect. In its complaint, the state charged that “several localities and civil rights groups … were ‘publicly hostile to cooperation with federal immigration enforcement.’”

That suit was mercifully dismissed in August. But the state’s strategy is instructive. One of the groups Texas sued along with Travis County was the Mexican American Legal Defense and Education Fund—one of the oldest and most respected Latino civil-rights groups in the country. I am quite sure that MALDEF has never refused an ICE detainer or refused to allow its peace officers to conduct immigration raids. (MALDEF has no jail, and no police force.) Its offense, the complaint stated, was that it “publicly declared imminent legal action against Texas.” (Texas was shamed into dropping MALDEF as a defendant even before the federal judge tossed the whole case.) It was as if Texas had sued the NAACP for opposing segregation.

Of course, that’s exactly what Southern states like Virginia did during the civil-rights era. That was another time of crisis, and the response of the segregated authorities was to attack the opposition. The state of Texas’s demand for silence and obedience echoes that dark time.

Immigration generally, and the Trump administration’s crackdown on the undocumented population in particular, are bitterly dividing both Texas and the United States as a whole. Much of the conflict pits urban areas against suburbs and rural ones; the cities where the undocumented live don’t want to drive their people into the shadows. Their officials believe that public services—such as civil justice, police protection, labor laws, public health, and consumer protection—can’t be effectively provided unless everyone can access them without fear of arrest or deportation.

In the past six months, the national disquiet over immigration has become a war against a new enemy: 11.3 million people within America’s borders. The Constitution’s guarantees of due process, equal protection, and security from unreasonable seizure or cruel and unusual punishment are being stripped from 3 percent of the U.S. population.

That war escalated sharply on Tuesday, when Attorney General Jeff Sessions announced that the administration is unwinding the “deferred action” program. The 800,000 “dreamers” in DACA—brought to the U.S. as children, raised among Americans—are now the enemy too. These are children, parents, brothers, sisters, co-workers, friends, and neighbors of American citizens. Whether at work, in emergency rooms, in courtrooms, at schools and colleges, or in their homes, unless Congress acts to protect them, they will be liable to arrest without warning and, often with only minimal due process, expulsion from the country.

Polls suggest that most citizens oppose wholesale deportation, and instead support giving law-abiding unauthorized immigrants a means to legalize their status, and eventually become citizens. As the war escalates, the outcry from local communities has begun. It seems unlikely this Congress will restore DACA; if it does not, the outcry seems likely to become louder. The war is probably unwinnable; it certainly is if Americans who oppose it are silenced. Courts do not save civil liberty when government is determined to stamp it out; for each citizen whose rights are vindicated in court, a dozen will remain silent out of fear. That is the meaning of “chilling effect,” and a chill wind indeed is blowing in the U.S. today.

“It is proper,” James Madison wrote in another context, “to take alarm at the first experiment on our liberties.” If citizens, and courts, do not act, Americans should not be surprised to find Texas-style gags around their mouths.