IN THE middle of America’s involvement in World War II, the Supreme Court faced down the Ashcrofts of that era when it invalidated a requirement that all schoolchildren start the day by pledging allegiance to the flag in order to perpetuate "the ideals, principles, and spirit of Americanism." A number of Jehovah’s Witness children, whose patriotism was not in doubt, refused to pledge because it violated the Biblical injunction against idol worship. In the 1943 case West Virginia Board of Education v. Barnette, Justice Robert Jackson, writing for a 6-3 majority, noted that the strength of the nation lay in "individual freedom of mind" rather than "officially disciplined uniformity for which history indicates a disappointing and disastrous end." As if responding to Ashcroft’s insistence that the administration’s wartime policies were beyond question, Justice Jackson warned that much misery has been caused throughout history by efforts "to coerce uniformity of sentiment in support of some end thought essential." Jackson concluded that "compulsory unification of opinion achieves only the unanimity of the graveyard."

A similar issue arose in the aftermath of the Korean War. We had defeated one deadly totalitarian system — Nazism — only to find ourselves in mortal conflict with another — Communism. State and federal loyalty oaths and investigations became the rage. In Sweezy v. New Hampshire (1957), the court ended the New Hampshire legislature’s investigation into the supposedly "subversive" views of professor Paul Sweezy, who had been held in contempt for his refusal to reveal, among other things, what he taught at the state university. His interrogators claimed that his teaching was subversive of New Hampshire’s democratic form of government. That era saw a host of similar, equally unsuccessful attempts to impose loyalty oaths on public employees.

The Vietnam War produced its own cases. While the court dealt harshly with people who actually interfered with the war effort — those who burned draft cards or urged others to do so, thereby disrupting the Selective Service System, for example — it assiduously protected those who questioned the war in even the strongest terms. Cohen v. California (1971), for example, authored by the great conservative justice John Marshall Harlan, protected the right of a young Californian to enter a courthouse with the slogan fuck the draft written on his jacket. The court recognized the difference between criticizing wartime policies and taking affirmative steps to interfere with then. Criticism does not aid the enemy; rather, it assures the health — and ultimately the security — of the nation.

So while it is true that historically some rights have been narrowed in wartime, it is also true that the modern-era Supreme Court has carefully preserved the right to criticize the government's wartime practices. Since World War II, the Court has held both that the text of the First Amendment provides virtually absolute protection for political speech — that "no law" means just that — and that the nation’s strength depends on what has been dubbed "the free marketplace of ideas," which serves as the most effective way to root out error. As Justice Jackson observed in Barnette, totalitarian societies were biting the dust not only because of internal enmity caused by efforts to enforce conformity, but also because conformity produced a false sense of security.

In the days just before Ashcroft’s Senate testimony, some former high-ranking FBI officials criticized Ashcroft and new FBI director Robert Mueller’s policy of mass arresting many hundreds of people thought to have connections with suspected terrorists. Such a policy, warned seasoned G-men, might actually interfere with investigators’ ability to follow such suspects, who could lead them to yet more terrorist cells. During his Senate testimony, Ashcroft tried to intimidate his critics by claiming that they give aid and comfort to the enemy. But while Ashcroft is free to use his bully pulpit to disagree with the administration’s detractors, his efforts to scare and silence them by labeling them disloyal actually detracts from our security. It seems, well, a bit unpatriotic. For, as the Supreme Court has long recognized, complacency and false certainty are the problem, while dissent and criticism are the solution.

Harvey Silverglate is the co-author of The Shadow University: The Betrayal of Liberty on America’s Campuses (HarperPerennial, 1999) and a partner in the law firm of Silverglate & Good.