Even in the immediate wake of 9/11, there were those who claimed that the Bush administration was "shredding the Constitution." Predictably, this chorus has only grown louder, with critics heaping scorn on the president and his attorney general, John Ashcroft, for their presumed indifference to civil liberties in the war on terrorism. For the most part, President Bush and Mr. Ashcroft have taken the abuse, but if they want to formulate a response, they might want to start with a remarkable letter that Abraham Lincoln sent to some of his critics during the crisis he faced.

The dilemma a president faces in time of emergency was expressed by James Madison in a letter to Thomas Jefferson: "It is a melancholy reflection that liberty should be equally exposed to danger whether the government have too much or too little power." Lincoln addressed this dilemma during his speech to a special session of Congress after Fort Sumter. "Is there," he asked, "in all republics, this inherent, and fatal weakness? Must a government, of necessity, be too strong for the liberties of its own people, or too weak to maintain its own existence?"

Throughout the history of the American republic, there has been a tension between two virtues necessary to sustain republican government: vigilance and responsibility. Vigilance is the jealousy on the part of the people that constitutes a necessary check on those who hold power lest they abuse it. As Thomas Jefferson wrote, "[I]t is jealousy and not confidence which prescribes limited constitutions, to bind those whom we are obliged to trust with power."

But while vigilance is a necessary virtue, it may, if unchecked, lead to an extremism that incapacitates a government, preventing it from carrying out even its most necessary and legitimate purposes, e.g. providing for the common defense. "Jealousy," wrote Alexander Hamilton, often infects the "noble enthusiasm for liberty" with "a spirit of narrow and illiberal distrust."

Responsibility, on the other hand, is the prudential judgment necessary to moderate the excesses of political jealousy, thereby permitting limited government to fulfill its purposes. Thus in Federalist 23, Alexander Hamilton wrote that those responsible for the nation’s defense must be granted all of the powers necessary to achieve that end. Responsibility is the virtue necessary to govern and to preserve the republic from harm, both external and internal. The dangers of foreign and civil war taught Alexander Hamilton that liberty and power are not always adversaries, that indeed, the "vigor" of government is essential to the security of liberty.

Lincoln’s actions as president during the Civil War reflected his agreement with this principle. Due to the unprecedented nature of the emergency created by the rebellion, Lincoln believed that he had no choice but to exercise broad executive power. Lincoln addressed the issue of civil liberties in wartime in a letter to Erasmus Corning (June 12, 1863), who had sent him the resolutions of the Albany Democratic convention. His arguments are as applicable today to the war on terrorism as they were in 1863 during a domestic insurrection.

The Albany Democrats had expressed loyalty to the Union but had censured the Lincoln administration for what it called unconstitutional acts, such as military arrests of civilians in the North. To the Albany Democrats’ claim that they supported the use of "every constitutional and lawful measure to suppress the rebellion," Lincoln replied that he had "not knowingly employed… any other" in the past nor did he intend to in the future.

The Albany Democrats invoked the safeguards and guarantees for the liberties of citizens under the Constitution, observing that they "were secured substantially to the English people after years of protracted civil war, and were adopted into our Constitution at the end of the revolution." Lincoln replied that their point would have been stronger had they said that these safeguards had been adopted and applied during the civil wars and during our revolution, rather than after the one and at the end of the other. "I, too," said Lincoln, "am devotedly for them after civil war, and before civil war, and at all times, ’except when, in cases of rebellion or invasion, the public safety may require’ their suspension."

Lincoln then argued that those who wished to destroy the Constitution were relying on the fact that "the government would, in great degree, be restrained by the same Constitution and law from arresting their progress." If anything, Lincoln continued, he waited too long to implement emergency measures. "[T]horoughly imbued with a reverence for the guaranteed rights of individuals, I was slow to adopt the strong measures which by degree I have been forced to regard as being within the exceptions of the Constitution, and as indispensable to the public safety."

The core of Lincoln’s argument is that the courts of justice are incompetent to handle cases arising out of a vast emergency. Suspension of habeas corpus is the constitutional provision that applies in such cases. The drafters of the Constitution understood, he continued, that there were emergency instances in which "men may be held in custody whom the courts, acting on ordinary rules would discharge." Habeas corpus does not discharge those proved to be guilty of a defined crime. The Constitution permits its suspension "that men may be arrested and held who cannot be proved to be guilty of defined crime, ’when in cases of rebellion or invasion the public safety may require it.’" This is because in times of emergency, arrests must sometimes be made not for what has been done, but to prevent things that probably would be done in the future.

Lincoln points out that a number of high-ranking Confederates, whose sentiments were then known, were in the power of the government when the rebellion broke out. Had they been seized, the rebellion would be weaker. But none of them had committed a crime defined in law, so they would have been discharged on the basis of habeas corpus if the writ had been permitted to operate. "In view of these and similar cases, I think I shall be blamed for having made too few arrests than too many."

The Albany Democrats had called the arrests of civilians in areas where the rebellion did not exist unconstitutional. Lincoln replied that the Constitution made no such distinction. His actions, he continued, were constitutional wherever the public safety required them, whether to prevent the rebellion from spreading, to prevent mischievous interference with raising and supplying the armies necessary to suppress the rebellion, to restrain agitators who sought to encourage desertion—in other words, his actions were "equally constitutional at all places where they will conduce to the public safety, as against the dangers of rebellion or invasion."

The Albany Democrats criticized the arrest and trial by military tribunal of the antiwar Ohio Democratic congressman Clement Vallandigham merely for his words. But Lincoln replied that Vallandigham was encouraging desertion from the army, on which the nation was depending to save the Union. He noted that the Albany Democrats supported the suppression of the rebellion by force. But this depends on an army, and one of the biggest problems armies face is desertion, an act so serious that it is punished by death. "Must I shoot a simple-minded soldier who deserts, while I must not touch a hair of a wily agitator who induces him to desert?"

Lincoln says that if he is wrong on the question of his constitutional power, his error is in believing that certain actions that are not constitutional in the absence of rebellion or invasion become constitutional when those conditions exists — in other words, "that the Constitution is not in its application in all respects the same in cases of rebellion or invasion involving the public safety, as it is in times of profound peace and public security."

Lincoln’s comment on the difference between times of emergency and times of peace should serve as a reply to President Bush’s critics:

I can no more be persuaded that the Government can constitutionally take no strong measures in time of rebellion, because it can be shown that the same could not lawfully be taken in time of peace, than I can be persuaded that a particular drug is not good medicine for a sick man, because it can be shown not to be good for a well one. Nor am I able to appreciate the danger apprehended by the meeting [of the New York Democrats] that the American people will, by means of military arrest during the Rebellion, lose the right of Public Discussion, the Liberty of Speech and the Press, the Law of Evidence, Trial by Jury, and Habeas Corpus, throughout the indefinite peaceful future, which I trust lies before them, any more than I am able to believe that a man could contract so strong an appetite for emetics during temporary illness as to persist in feeding upon them during the remainder of his healthful life.