President Obama wasted no time in halting detainee trials before military commissions in Guantanamo. Good. He will soon be confronted with a range of ideas for dealing with the detainees there–including prosecuting them in special “national security courts” that will supposedly offer justice while keeping classified evidence out of the public view.

Obama needs to recognize that establishing such courts is a recipe for both bad law and bad policy. Along with numerous compelling legal arguments, any court outside of existing civilian or military systems only serves to exaggerate the power of extremist terrorists and validate their delusions of grandeur.

Proponents of national security courts often point to the Foreign Intelligence Surveillance Court (FISC), which reviews requests for surveillance warrants against suspected foreign intelligence agents. The FISC uses judges with high-level security clearances that, as some proponents argue, could be used as the backbone for a new court system to try the detainees. The trials would be largely closed to the public and would not use a jury.

Using closed courts to try suspected terrorists plays the propaganda game in exactly the way our enemies want, and cheapens American justice on the world stage. Terrorism and insurgency constitute violence with a message. To effectively counter terrorists, we must provide a message of our own that denies a propaganda victory to their cause. Meting sound and irreproachable justice is an important way to do that.

While American forces are constantly improving their counterterrorism and counterinsurgency methods, we remain ineffective in countering enemy propaganda in the field of “lawfare.” Lawfare is the use of international law to attack nation-states in courts of law and public opinion. The Taliban do this every time they hide behind civilians and then denounce Coalition forces for the inevitable and regrettable casualties. Guantanamo represents a self-inflicted lawfare wound against the United States, where the limbo between domestic criminal law and the law of war erodes at America’s values and international standing.

While serving as a Special Forces officer in Afghanistan, I took into account the Taliban’s propaganda purposes when planning operations. They didn’t need to kill us to win a small victory. They needed to shoot at us and run away to tell the tale, where fishing stories of exaggerated casualties could encourage ever larger groups of radicalized fighters to attack the Afghans and their American allies.

Khalid Sheikh Mohammed had lawfare in mind when he and several co-defendants tried to plead guilty to the Military Commissions and ask for the death penalty. This constituted one final martyrdom mission where he could complain to the world about his treatment before a kangaroo court. We must not give him his final moment of glory.

Instead, transfer Khalid Sheikh Mohammed into an existing court along with the other detainees we have enough evidence to try. Courts-martial are the envy of the world’s military justice systems. Better yet, use the federal court system; nothing destroys Al Qaeda’s message better than a jury trial. A co-equal branch of government, represented by a life-tenured judge not beholden to the president, using a jury of average American citizens, weighing the evidence and coming to a guilty verdict–that is effective counter-lawfare.

Federal courts are fully able to handle such cases. They have successfully prosecuted over a hundred terrorism cases since 9/11, attaining over a 90 percent conviction rate. Using the Classified Information Procedures Act (CIPA), federal courts can exclude classified information or offer it in a redacted or unclassified version to protect government interests. Federal courts have proven flexible and successful with CIPA, special detention rules, jury security measures, and exceptions to domestic law that mean we won’t have to read Miranda rights to future detainees.

The Founders wrote the Bill of Rights after a violent insurgency brought on by government oppression, and the principles contained therein are no weaker while countering today’s terrorists. Using national security courts to try the detainees in Guantanamo opens the door to closed and classified trials of domestic terror suspects. This degradation of essential liberties is unwise and avoids the social function of trials: to show the world–not just a judge in his chambers–that the defendant is guilty and deserves our condemnation.

In the current war of images, Al Qaeda struck a terrible blow with airplanes smacking into the sides of skyscrapers. Since that awful moment, America has a mixed record in the battle of opposing pictures and video clips, with Abu Ghraib and Guantanamo effectively offsetting the purple fingers of voters in new democracies. Let the next image–Khalid Sheikh Mohammed marching off to life imprisonment with a federal marshal at his side–follow an open trial with declassified versions of the necessary evidence, not a hearing behind closed doors.