IT IS NO secret that the War on Terror's prosecution has revealed fundamental differences between the United States and Europe over how to meet the challenges of global terrorism and jihadi Islamism. After the September 11 attacks, the United States chose a military response and considers itself to be engaged in a legally cognizable armed conflict to which the laws and customs of war apply. That view, although occasionally questioned by American politicians like Senator John Kerry (D-MA) during his unsuccessful 2004 presidential campaign, is supported by most Americans and is not likely to change regardless of who moves into the White House on January 20, 2009. This public sentiment aside, the nature of the American civilian legal system, which features many procedural and substantive protections that make it difficult to prosecute wartime combatants, especially those captured overseas, as well as the need to prevent rather than simply to punish terrorist attacks, effectively requires adoption of a war-fighting over a law-enforcement approach to transnational terror.

By contrast, governments Left and Right in Europe have evinced a clear preference for treating Al-Qaeda and other jihadists as a difficult, but manageable, political or law-enforcement problem. Moreover, not content with a "live and let live" strategy, they have sought to impose their legal and normative preferences on the United States and have reacted with varying degrees of disappointment, dismay and outrage at the Bush Administration's war policies. This is especially true of the president's decisions to classify captured Al-Qaeda and Taliban operatives as "unlawful enemy combatants", to detain them without criminal charge at Guantanamo Bay and to try them in military commissions rather than in civilian courts. If anything, attitudes in Europe have hardened since Congress enacted the Military Commissions Act of 2006. This law provides an explicit statutory basis for the president's policies and effectively vitiates the oft-invoked criticism that he employed the wartime legal paradigm solely on his own constitutional authority.

But more is at stake here than a tactical spat over how to deal with Al-Qaeda. There seems to be little doubt that Europe, or at least the European Union's leading countries, is consciously playing for the West's moral leadership, and Europe believes that it can win. Like it or not, the United States is now engaged in an ideological struggle resembling in some respects the ideological battles of the Cold War except that, this time, its closest friends and relations are in the opposition. Ask any cop on the beat; there is nothing more dangerous or dirty than a family fight, but this is a fight America must accept and win-for everyone's sake.

THE TRUTH is that, despite NATO's invocation of Article 5, accepting September 11's Al-Qaeda strikes as armed attacks against a member state, Europe has never thought of the War on Terror as a real war. As a high-ranking continental official once told the authors with feeling, "September 11 was a crime. It was a very great crime, but it was a crime."

The causes of this fundamental transatlantic difference in perspective appear to be twofold. First, Europe has had more experience with terrorist threats (albeit of the homegrown variety) than the United States and has managed to muddle through-although at a cost-without declaring a "war" on terror. In this regard, most European legal systems are simply better suited to investigating, interdicting and ultimately punishing terrorists than are America's civilian courts. Second, war has itself become an unacceptable concept in Europe, which has adopted so many legal limitations on the use of armed force that it is hard to imagine how European militaries could prevail in a serious conflict against a determined and ruthless transnational terror organization like Al-Qaeda. In a very real sense, Europe has not merely adopted a counter-terrorism model for law enforcement, it has also imposed the rules governing policing on its military forces, and it now expects the United States to follow suit.

Bonaparte's Justice-or the Founding Fathers'?

WITH THE notable exceptions of England and Ireland, Europe largely follows the civil-law criminal justice model, usually based today on some version of France's Code Napoleon. That system is grounded in Roman law and relies on an "inquisitorial" process-where the judges are active participants in finding the truth-for determining an accused offender's guilt or innocence. On the other hand, the common-law system, followed in England and many of her former colonies including the United States, uses an "adversarial" criminal procedure where judges act more as referees than investigators.

Overall, the civil-law system offers considerable advantages to the state in combating terrorism-especially in terms of investigative tools and a level of secrecy-that are simply unavailable in the ordinary common-law criminal prosecution and trial, at least as governed by the U.S. Constitution. And, while the law-enforcement model is never an optimum approach to dealing with global terrorist organizations that can project power and use force on a scale comparable to a traditional armed conflict, the European version of this model is at least semi-workable.

Civil-law criminal trials are not conducted before a jury in public as required by the U.S. Constitution's Sixth Amendment. Although serious offenses are almost always tried before a panel of three or more judges, and a number of civil-law jurisdictions (such as France) also provide for the participation of "lay" advisors or assessors, the civil-law fact-finding phase-during which much of the record is assembled-is fundamentally different than in common-law countries. In the United States, the record upon which the accuser's guilt or innocence is determined is compiled during the trial itself, with the judge acting as a legal umpire and the jury the ultimate arbiter of fact. In this process, the source, nature and legal sufficiency of all evidence is critical, as the jury can only find the facts based upon evidence that is, and has been, determined to be admissible and presented in open court.

By contrast, in civil-law systems, the record is made through a process of inquiry (or inquisition) by an investigating judge or magistrate. Throughout this stage of proceedings, the magistrate is assisted by the police, who act under his direction. (The police are also, of course, involved in the pre-judicial phases in identifying the suspect and providing sufficient evidence to the prosecutor who determines whether to refer the case to an investigating judge.) In France, for example, although there are certain limits to when and how a search can be conducted, the police do not need a search warrant-in the form of a judicially issued, particularly defined order based on a probable-cause showing-to obtain evidence from or against a suspect.

Moreover, the investigating magistrate has broad authority to seek out almost any information he believes will assist in establishing the truth. Although the trial record in an American criminal case consists only of the legally admissible evidence presented by the prosecution and defense before judge and jury, the civil-law record (which will at least be available to the trial judges, although not necessarily to any lay assessors) includes all the evidence the investigating magistrate considered to be useful in determining what actually happened.

In addition, introduction of evidence into the record is not limited by the type of very narrow evidentiary rules prevailing in the United States. The civil-law trial bench usually has broad discretion to allow inclusion of any evidence it considers useful for determining the truth. Thus, for example, hearsay evidence is commonly accepted as part of the record in civil-law countries, even though its admission in the United States (apart from certain exceptional circumstances) would be considered a violation of the defendant's right to confront the witnesses against him.

Also, this critical investigative stage of the proceedings is conducted in private. Access to the file is eventually granted to defense counsel-in France, for example, shortly before the suspect is first formally examined as the accused-although much of the investigatory work will have very likely been accomplished by this time. However, as a rule, there is no public right of access. The trial itself, where the record is supplemented by the oral testimony and argument on which a decision is supposed to be based, is generally public, although these proceedings can also be closed for reasons of public policy or public morality. This, of course, is another critical difference between the civil-law system and common-law jurisdictions, where the record is made at trial and in public with the narrowest of exceptions.

The civil-law investigating judge can also order pre-trial or "investigative" detention for the accused. This authority, which (in France at least) is supposed to last no more than a year but can involve much longer periods, is widely used. There is no constitutionally mandated presumption for a reasonable bail in most civil-law jurisdictions as there is in the United States. Indeed, very lengthy pre-trial detention is one of the most common and persistent human-rights abuses identified in the State Department's annual human-rights country reports with respect to the major European democracies. From 1999 through 2005, for example, lengthy pre-trial and trial detention was identified as a problem in Spain, France, Italy and Belgium-and could be fairly described as especially acute in the latter three countries. In 2005, 35 percent of the French prison population were individuals awaiting trial; in Italy, nearly 40 percent were pre-trial detainees, 38 percent in Belgium and 20 percent in Spain.