Apocalyptic predictions for the gathering battle over the next Supreme Court appointment have led political conscientious objectors to urge the White House and the Senate to practice “moderation,” “conciliation” and “compromise” — in other words, to back off from brinkmanship tactics. But if we stop to consider how much power each justice wields, the president and the Senators both ought to have their war faces on.

The Supreme Court of the United States is the most powerful judicial body in the world. Each justice shares in the power of judicial review that amounts to the ability to interpret and, in a sense, amend the Constitution without the people’s consent.

Article V of the Constitution provides the procedures for making formal amendments: They must be approved by a two-thirds majority in both houses of Congress and ratified by the approval of three-fourths of the state legislatures. Only 27 formal amendments have been proposed and ratified in more than two centuries, however, and only 17 of those have come since the adoption of the Bill of Rights.

Since 1803, when the Supreme Court claimed the power of judicial review in the landmark decision of Marbury v. Madison, an alternate way of changing the meaning of the Constitution has existed: a simple majority vote by five of the nine justices. Indeed, judicial edicts have accounted for many times more changes in constitutional law than the formal amendments have. The Supreme Court has overturned more than 150 acts of Congress and more than 1,000 state and local laws; the justices have overruled themselves more than 200 times. “We are under a Constitution,” former Chief Justice Charles Hughes said, “but the Constitution is what the judges say it is.”

Often these changes have had profound consequences, such as Brown v. Board of Education, the 1954 decision that declared an end to “separate but equal” racial apartheid. That historic decision was unanimous. But some of the most controversial issues of the day are in fact decided by a one-justice margin, such as last year’s decision supporting racial affirmative action in college admissions and the decision that stopped the Florida recount in the 2000 presidential election.

The Supreme Court majority’s preferences determine national policy on many important and divisive issues, such as abortion, euthanasia, the death penalty, remedies for discrimination, and the separation of church and state. And, as Justice Robert Jackson once noted, there is no further appeal: “We are not final because we are infallible; we are infallible only because we are final.”

Any combination of five justices voting together wields a power comparable to the supermajorities in the House, Senate and state legislatures. That means that five justices cumulatively count as much as 67 Senators, 290 Representatives and 38 state legislatures.

Thus, every time the president nominates and the Senate confirms a new justice, it amounts to a sea change in the distribution of power. Only the election of a president — arguably — is politically more significant.

Justices serve “during good behavior,” effectively for life; Chief Justice William Rehnquist, to take just one example, was appointed by Richard Nixon in 1971. In 1805, the House impeached Justice Samuel Chase, but the Senate acquitted him and the understanding ever since has been that a justice cannot be removed for his or her decisions. Thomas Jefferson concluded that judicial impeachment was an impractical threat, a “mere scarecrow.”

The point is this: The nomination and confirmation process is our last chance — indeed, our only real chance — to pass judgment on high court justices.

What Karl von Clausewitz said about war applies to constitutional interpretation: “It is a continuation of politics by other means.” Every Supreme Court appointment is a critical battle in the Kulturkampf. The opposing sides are gearing up for more than an academic lyceum. The president should take his best shot. So should the Senate. Then “We the People” should get ready to choose sides in the coming political fight over the influence and the direction of the Supreme Court.

Thomas E. Baker is a member of the founding faculty at the Florida International University College of Law, where he teaches constitutional law.