Torture. Carpet-bombing. A "real war on terror." Political campaigns are notoriously brutal contests, but some of the current campaign rhetoric suggests that several candidates have adopted the idea of brutal methods straight into their national security discourse. Indeed, Donald Trump (R) seems proud to declare that waterboarding would be merely an introductory interrogation technique in a toolkit of ever more abhorrent options.

The dangers of this rhetoric are enormous. Torture is illegal. Torture is illegal under U.S. law, international law and other national laws. Torture is illegal during wartime, peacetime, counterterrorism operations and any other circumstances.

For two centuries until 9/11, the United States enforced these prohibitions on torture and inhuman and degrading treatment, beginning with courts-martial under the Articles of War during the Revolutionary War and formal codification of the prohibition of torture in the Lieber Code, the rules for warfare that President Abraham Lincoln commissioned during the Civil War. No less, we prosecuted American service-members for waterboarding — the very tactic at issue today — during the counterinsurgency campaign in the Philippines at the turn of the 19th century. After World War II, the U.S. and its allies convicted hundreds of Japanese leaders and soldiers for waterboarding and other forms of torture employed against U.S. and allied personnel. The public condemnation of such tactics as the basest violations of law and morality was equally resounding.

The law of war — the law that governs how warring parties conduct hostilities and treat all persons during armed conflict — has matured into a remarkably robust and comprehensive legal framework over the past century. And yet somehow, even after the Senate's comprehensive investigation into and public condemnation of torture and other abuses the U.S. used against al Qaeda and other detainees, even after new laws, executive orders and policies reaffirming the prohibition against torture and similar techniques, our national dialogue has once again regressed to the point where we seem to talk only about the potential effectiveness of methods that have been roundly condemned for two centuries.

Effectiveness is not the issue. Law is not one factor in many to be weighed in the decision-making process. Law sets the parameters for state and individual action — and within those parameters, we reach decisions based on resources, the effectiveness of different options, and a host of other considerations. Talk of effectiveness suggests that law is simply a consideration, one that can be discarded when it proves too onerous or irritating. It is hard to imagine a more damaging conception to the entire enterprise of the rule of law and protection of fundamental rights and human dignity.

Beyond that, it is essential to understand that these fundamental rules are not simply words in a treaty the U.S. signed or a law Congress enacted. These rules, and the morality on which they rest, are the essence of leadership in difficult and challenging times.

Talk of leaders protecting American values is common. The role of a leader in protecting values and morality, whether the president of the United States or a small unit commander in the Marine Corps, is the most vital in times of war, when the violence and brutality of an enemy threaten us physically and calls for no-holds barred tactics threaten our values and moral fabric.

Experience demonstrates that U.S. adherence to and enforcement of the law of war — including the prohibition on torture and cruel, inhuman or degrading treatment with regard to all persons, including terrorists — protects members of our military when engaged in combat or other operations overseas. Simply put, our soldiers, sailors, airmen and Marines receive better treatment at the hands of others when the United States steadfastly adheres to the key principles of international and domestic law.

But leadership is not only about protecting the American people physically by any means necessary. It is about protecting the American people, American service-members and the very idea of America itself by ensuring that we conduct ourselves in a manner that reaffirms our values and enables the continuation and flourishing of a nation and society built on the rule of law. Law and the values on which the law is based play a critical in protecting the morality of our troops and others on the front-lines of the struggle against transnational terrorism.

Army Gen. Telford Taylor, the U.S. chief prosecutor at the Nuremberg Tribunal, explained:

War is not a license at all, but an obligation to kill for reasons of state; it does not countenance the infliction of suffering for its own sake or for revenge. Unless troops are trained and required to draw the distinction between military and nonmilitary killings, and to retain such respect for the value of life that unnecessary death and destruction will continue to repel them, they may lose the sense for that distinction for the rest of their lives.

These men and women, asked to accomplish extraordinary goals on behalf of the state, must also come home and reintegrate into society at the end of deployment or service. By providing a framework for moral and operational choice, the law helps to preserve and protect their moral core. Indeed, these fundamental rules are not only about what happens to our enemy when we fight, but what happens to us when we fight. Tough talk of torture, enhanced interrogation techniques and carpet-bombing may make good campaign copy, but such rhetoric and acts not only violate the law, but ultimately undermine the very essence of leadership and morality.

Blank is a clinical professor of law and director of the International Humanitarian Law Clinic at the Emory University School of Law. This article was originally published on The Hill.