Martha Crenshaw is a pioneer in terrorism studies, one of a handful of scholars worldwide who started investigating the subject long before Sept. 11, 2001.

Crenshaw, who joined CISAC this year as a senior fellow at FSI and a political science professor by courtesy, brings three decades of study to her current agenda of examining distinctions between so-called old and new terrorism, how terrorism ends, and why the United States is the target of terrorism.

"We are very fortunate to have Martha Crenshaw join CISAC as a senior fellow," said Scott Sagan, CISAC co-director. "Her detailed knowledge of the inside workings of terrorist organizations and her deep understanding of earlier counter-terrorist campaigns have brought much-needed historical perspective to contemporary policy debates after 9/11."

Associate professor of law Mariano-Florentino Cuéllar, who led the search that resulted in Crenshaw's hiring, said her "combination of attention to historical detail, interdisciplinary methods, and knowledge of institutional context has made her one of the nation's foremost scholars of terrorism. Her appointment is great news for CISAC and Stanford, where she will strengthen an already significant scholarly community working on homeland security and terrorism."

Coming to Stanford from Wesleyan University, where she was the Colin and Nancy Campbell Professor of Global Issues and Democratic Thought and a government professor, Crenshaw said she found the opportunity to join an interdisciplinary research center a welcome change.

"CISAC's and my interests merged perfectly," she said, as the center was looking to build its research expertise in terrorism. She said she looks forward to teaching graduate students in the Ford Dorsey Program in International Policy Studies as well as working with research colleagues at CISAC and across campus.

Crenshaw's terrorism studies began with a graduate seminar paper she wrote on actions by the FLN, or National Liberation Front, during Algeria's war for independence from France in the 1950s and 60s. She arrived at the topic the way many professors advise students to do--she noted in a study of Vietnam-era guerrilla warfare the comment that "no one has studied terrorism."

That seminar paper inspired her dissertation, which formed the basis of her 1978 book, Revolutionary Terrorism: The FLN in Algeria, 1954-1962, a case study in the strategic use of terrorism by a revolutionary nationalist movement.

Having written numerous articles and edited four books on terrorism, Crenshaw is now editing a book tentatively titled The Consequences of Counterterrorist Policies in Democracies. The Russell Sage Foundation supported the research, which Crenshaw said illuminates issues such as "the strength of executive power, effects of counterterrorism legislation on minorities, and unintended consequences of counterterrorism policies."

As a lead investigator with the National Consortium for the Study of Terrorism and Responses to Terrorism at the University of Maryland, a Department of Homeland Security Center of Excellence, Crenshaw is also researching why the United States is the target of terrorism, a study that could be especially useful in informing counterterrorism policy.

Crenshaw "trace[s] the evolution of anti-American terrorism over time--since the mid-1960s," she said, comparing groups that used terrorism to others with similar ideas that have not resorted to terrorism. Comparing case studies, she explained, allows her to "analyze incentives for the use of terrorism."

In "The Debate over 'New' versus 'Old' Terrorism," a paper Crenshaw presented at the American Political Science Association annual meeting in September--and which will be published as a chapter in an edited volume, she questions oft-heard claims that terrorism in recent years has taken on a new character to become more religious and lethal. She found the distinctions too hastily drawn and possibly dangerous.

"There is no fundamental difference between 'old' and 'new' terrorism," she said.

"Rejecting our accumulated knowledge of terrorism by dismissing it as 'obsolete'" would be a mistake that could lead to bad policy choices, she added. Before 9/ll, assumptions that "new" terrorism would forsake the "old" technique of hijacking and turn to weapons of mass destruction turned out to be wrong, she pointed out.

Crenshaw said researchers and policymakers should "ask why some groups cause large numbers of civilian casualties and others do not, rather than assuming that religious beliefs are the explanation for lethality."

Before attacking Iraq in March 2003, the United States told the world that Saddam Hussein had reconstituted his nuclear weapons program in defiance of the United Nations. That claim, used to justify the war, was based on assessments provided by the United States intelligence community. But as everyone now knows, those assessments were wrong. So Jeffrey T. Richelson's history of American nuclear intelligence, including our attempts to learn about Iraq's nuclear program, could hardly be more timely.

In "Spying on the Bomb," Richelson, the author of several books on American intelligence, has brought together a huge amount of information about Washington's efforts to track the nuclear weapons projects of other countries. He examines the nuclear projects of Nazi Germany, the Soviet Union, China, France, Israel, India, South Africa, Taiwan, Libya, Pakistan, Iran and North Korea, as well as Iraq. Through interviews and declassified documents as well as secondary works, he sets out briefly what we currently know about those projects and compares that with assessments of the time.

This may sound like heavy going, but Richelson writes with admirable clarity. And along the way he has fascinating stories to tell: about plans to assassinate the German physicist Werner Heisenberg during World War II; about discussions in the Kennedy and Johnson administrations on the possibility of attacking Chinese nuclear installations; about Indian measures to evade the gaze of American reconnaissance satellites; and about the bureaucratic infighting over the estimates on Iraq.

The United States has put an enormous effort into gathering information about the nuclear projects of other countries. After World War II it equipped aircraft with special filters to pick up radioactive debris from nuclear tests for isotopic analysis. It created a network of stations around the world to register the seismic effects of nuclear explosions. Most important, in 1960 it began to launch reconnaissance satellites that could take detailed photographs of nuclear sites in the Soviet Union and China. Richelson occasionally speculates about the role of communications intercepts and of spies, but these appear from his account to have been much less important than the other methods of collecting information.

Through these means the United States has gathered a vast quantity of data, sometimes to surprising effect. Intelligence played a crucial role in the cold war, for instance, by reducing uncertainty about Soviet nuclear forces. Alongside such successes, however, there have been failures. One notable example concerned the first Soviet test, which took place in August 1949, much sooner than the C.I.A. had predicted. Another was the failure to detect Indian preparations for tests in May 1998, even though at an earlier time the United States, with the help of satellite intelligence, had managed to learn about preparations the Indians were making and to head off their tests.

But the most serious failure of all was in Iraq in 2003, because in no other case did the intelligence assessments serve as justification for the use of military force. The information needed for avoiding political surprise is one thing. That needed for preventive war is quite another, if only because of the consequences of making a mistake.

Beyond making the uncontroversial recommendation that "aggressive and inventive intelligence collection and analysis" should continue, Richelson draws no general conclusions. That is a pity, because his rich material points to issues that cry out for further analysis. He suggests in one or two cases that failures sprang from the mind-set of the intelligence community, but he does not elaborate on this point. He has little to say about relations between policy makers and the intelligence community, even though the quality of intelligence and the use made of it depend heavily on that relationship.

His focus is no less narrow in his discussion of foreign nuclear projects. He concentrates on the programs themselves, paying very little attention to their political context. Does that reflect a technological bias in nuclear intelligence? Would, for example, the prewar assessment of Iraqi nuclear capabilities have been more accurate if it had paid more attention to the broader political and economic circumstances of Hussein's regime?

The task of intelligence has become more complex than it was during the cold war. A single dominant nuclear opponent has now been replaced by a number of nuclear states, along with states and stateless terrorists that are aiming to get their hands on nuclear weapons. Meanwhile, the technology needed for producing nuclear weapons has become easier to acquire.

Many critics believe the recent performance of the intelligence community shows it has not responded adequately to this new situation. Richelson does not have much to say on this question; nor does he discuss the likely impact of the current reforms, initiated in response to the Iraq war, on the quality of intelligence. His reticence may imply that he does not think reform is necessary. Still, it is disappointing that he does not draw on his historical survey to discuss whether new approaches are needed for dealing with nuclear threats, and, if so, what those new approaches might be.

Earlier this month, the so-called EU Three--Britain, France and Germany-- achieved an important victory for global security, convincing Iran to suspend its uranium enrichment and plutonium reprocessing activities pending further negotiation on its nuclear question. Though Iran claims that it does not desire a nuclear bomb, the West has long been skeptical of the oil-rich state's contention that it seeks a nuclear fuel cycle for energy purposes alone. Europe and the United States (and of course Israel) will sleep better knowing that Tehran is not pursuing enrichment activities, whatever their alleged purpose.

But the EU3 agreement, which fails to discuss consequences for Iran if it breaks the deal, is vulnerable to being undermined not only by Iran but also by the United States; both have already raised eyebrows in the wake of the accord. Iran raced to produce uranium hexafluoride, a gas that can be enriched into bomb fuel, before it began to observe the temporary suspension on Monday. And both President George W. Bush and outgoing Secretary of State Colin Powell have publicly aired their suspicions that Iran will continue its drive for nuclear weapons under cover of the deal.

At the moment, administration hawks are pressing to confront the mullahs at the United Nations Security Council, where economic sanctions could be considered; calls for using force and for regime change are likely to follow.

Military action is inadvisable at this point, because of a dearth of solid intelligence and the secretive, geographically diffuse nature of Iran's nuclear sites. If the issue reaches the Security Council with the United States and Europe continuing along divergent paths, the inevitable deadlock will deal a severe and lasting blow to international security. Therefore, the agreement must be fortified to keep the Iranians honest, the Europeans effectively engaged and the U.S. hawks bridled.

This can be achieved through a U.S.-European accord laying out trigger mechanisms for specified consequences if Iran violates certain benchmarks. For example, if Iran fails to allow inspectors the access accorded by the Nuclear Nonproliferation Treaty's additional protocol--which Iran is provisionally observing pending ratification--or resumes enrichment and centrifuge-building activities, it could face severe economic sanctions, censure by the Security Council (necessitating cooperation from Russia and China), or in the event of hostility, a forceful response.

We don't know yet whether Tehran will play by the rules. The regime has mastered the art of behaving badly and then seeking rewards for getting back into line. To date, the Europeans have played into its hands, offering carrots for compliance without wielding sticks to punish violations.

Therefore, the Bush administration's apparent comfort with a military option can serve as an important deterrent against Iranian cheating, arming the EU3 agreement with teeth that it would not otherwise have. Iran desires economic incentives but does not yet desperately need them; without a credible threat of U.S.-backed sanctions imposed by the international community, the mullahs can simply decide one day that the restrictions have ceased to be worth their while, and break any deal as though it were merely a business contract.

For the United States, accepting the EU3's carrot-based approach (provided the benchmarks are added) will show the world that it still supports negotiated diplomacy and multilateralism, even in cases where military threats loom. Participating in this framework will also send a message to Iran that the United States is not ruling out renewed relations. This would resonate with the largely pro-American Iranian populace, who despise their regime and are seeking inroads to break free of it.

But if the United States instead presents itself as a unilateralist maverick, it will hinder its own interests; the only thing Iranians disdain more than the mullahs is outside meddling with their deeply nationalistic desire for self-determination. The more overtly hostile the United States acts toward Iran, the more the mullahs are able to spin America's posture to alienate Iranians against the "Great Satan."

The way to keep the Iranian regime in check while speeding its demise is to insure the nuclear agreement through benchmarks and triggers, and then give the mullahs exactly what they ask for in terms of increased access to international institutions like the World Trade Organization.

Such carrots can also be Trojan Horses, allowing the forces of democratic reform within Iran to blossom by enabling pro-democracy elements to make global connections. The U.S. and Europe should saddle up those horses together.

We've been down this road before: A crisis threatens global security, and the international community is not coming together to deal with it. Hawks in the U.S. administration see the Europeans as too timid to use force and reliant on diplomacy to a fault, while many Europeans see the United States as trigger-happy and too impatient with negotiated settlements. This lack of cohesion damaged the legitimacy of the American-led war in Iraq and left U.S.-European relations in tatters. A similar disunity jeopardizes current attempts to manage Iran's nuclear aspirations, even though both sides agree that the threat posed by a nuclear Iran is grave and real.

Departing Deputy Secretary of State Richard L. Armitage positively spun the divergent U.S. and European approaches to Iran: "The [diplomatic] incentives of the Europeans," he said, "only work against the backdrop of the United States being strong and firm on this issue. In the vernacular, it's kind of a good cop/bad cop arrangement. If it works, we'll all have been successful." The problem with Armitage's hopeful outlook is that the good cop/bad cop strategy works only if pursued consciously and in coordination, and the U.S. and European approaches do not reflect that yet. In fact, they seem headed in opposite directions.

The good cops--Britain, France and Germany--recently persuaded Iran to suspend all uranium enrichment-related activities until they reach a final accord. If the mullahs cooperate, they will receive numerous economic carrots, including possible membership in the World Trade Organization (the U.S. would have to agree) and improved trade relations.

In October 2003, when the International Atomic Energy Agency was prepared to take its negative report on Iran's nuclear program to the U.N. Security Council, the mullahs cut a similar deal with the Europeans, promising to suspend all enrichment-related activities. But Iran soon grew impatient with the agreement and resumed efforts to produce the gas that feeds uranium enrichment. It similarly rushed to make as much of that gas as possible before the latest accord's deadline, undercutting confidence in the deal on both sides of the Atlantic. In another bad-faith move, Iran announced last week that it wanted to keep operating uranium-enrichment equipment for research purposes, backing off its pledge to freeze all such activities.

Enter the bad cop--the United States. It has pushed to refer the question of Iran's nuclear aspirations to the Security Council. When Secretary of State Colin L. Powell steps down, the hawkish voices in his department will probably intensify and gain influence, especially if the mullahs break the newest deal.

Armitage might be right that the discordant U.S.-European approaches will push the mullahs to hold to the deal. But the U.S. will be uncomfortable with an agreement that does not insist on any means of enforcement or verification, as is the case with the latest accord.

Iran knows that the war in Iraq colors U.S. conduct toward it. The worse Iraq gets, the less Iran worries--and the mullahs don't seem too worried at the moment. But if they break the accord with the Europeans and the Europeans respond timidly and U.S. resources are freed up as a result of an improving situation in Iraq, the U.S. could take on Iran alone--to everyone's detriment. To avoid this risk, the U.S. and Europe need to harmonize their approaches and develop a coordinated strategy for Iran. The best way to accomplish this is to agree in advance on the consequences Iran will face if it violates its commitments. For example, if the mullahs renege on the latest deal, frustrate the monitoring and verification efforts of IAEA inspectors or fail to ratify an addition to the Nuclear Non-Proliferation Treaty that allows for more invasive inspections, the U.S. and Europe should go to the Security Council, impose economic sanctions or, in the worst case, take military action.

Fortunately, diplomatic disunity over Iran does not run as deep as it did over Iraq, where even the nature of the threat was a bone of contention. Both the U.S. and Europe are worried about a nuclear Iran, and they feel strongly about enforcing the rules of nonproliferation. In June 2003, European foreign ministers required only 45 minutes to approve a document that endorsed U.N.-sanctioned use of force as a last resort against proliferators, as well as "political and diplomatic preventative measures."

If the Europeans agree to leave all responses on the table and to act decisively at the first sign of Iranian mischief, the United States would be foolish not to form a partnership with them. (It's also important that the U.S. set a better example as a member of the nonproliferation community by abandoning plans to build new mini-nuclear weapons and ratifying the Comprehensive Test Ban Treaty.)

The role the U.S. forges for itself in dealing with Iran will have significance beyond reinvesting in international order or responding to the mullahs' nuclear ambitions. Iran's despotic regime will collapse some day, and there will be a "morning after" similar to that in Iraq, where reconstruction efforts have floundered because U.S. planners underestimated the challenge of nation-building and the need for international support to make it work. When Iran makes its move toward a better government, the U.S. should be in a position to lead a coherent, collective international effort to help it get off the ground.

Yet since the severing of U.S.-Iranian ties in 1980, the U.S. has been slack in developing a viable Iran policy. Iran's nuclear ambition should be motive enough to reverse this inattention. U.S. policy toward Iran must cease to be reactive, as it is now.

In addition to working with the Europeans to curb the mullahs' nuclear efforts, the U.S. should begin crafting a strategy to work toward--and then with--a democratic Iran. Supporting a government that complies with its international obligations is certainly preferable to containing one that thwarts them. By getting involved now, the U.S. can do much to show Iranians that it will be a friend to a free Iran. A democratic Iran may still want a nuclear bomb as a matter of national pride. But a less threatening, pro-diplomacy U.S. would be in a stronger position to argue the benefits of membership in the nonproliferation community rather than life as a rogue power.

Participating in a multilateral approach to Iran's nuclear program is a great place to start. In doing so, the U.S. will signal to Iranians that its aggressive position does not reflect a desire to remake Iran in its own image but rather a desire to achieve, alongside Europe, a substantial victory for nonproliferation and international security.

Faced with the deadly menace posed by transnational terror organizations, the nations of the world must redouble their cooperative efforts. The tasks ahead -- to disrupt terror groups and preempt their attacks -- require intense coordination among a multitude of national intelligence, national law enforcement, and military organizations. Unprecedented cooperation among all of the nuclear powers is needed to prevent nuclear weapons from falling into the hands of terror groups.

Yet, paradoxically, the two nations that have suffered the worst terror attacks -- the United States and Russia -- are regressing more and more to national strategies. They have been unwilling to make the extra effort to reap the benefits of real international cooperation.

I believe that the United States' strategic vision of the war on terrorism is flawed. I fear it is following the isolationist path of the United States after World War I rather than pursuing the broad international programs it successfully undertook to protect its security interests after World War II.

The terrorists posing the greatest threat to the United States and to Russia are transnational, with cells in many different countries. To support their training and operations, they raise funds in many countries and maintain these in international bank accounts. They use satellite-based television as their principal means of propaganda, the World Wide Web as their principal means of communication and international airlines as their principal means of transportation. Their efforts to get weapons of mass destruction are based on penetrating the weakest security links among the nations possessing these weapons, and their successful guerrilla operations depend on their ability to get support from sympathizers among the more than 1 billion Islamic people around the world.

An international operation is clearly needed to successfully deal with this threat. But the United States is not making full use of other nations and international institutions to dry up the terrorists' funds in international bank accounts, to gain intelligence on their planning for future attacks, to penetrate their cells so that it has a chance of preempting these attacks, to organize all nuclear powers with effective security of their nuclear weapons and fissile material, and to conduct counterinsurgency operations wherever they are needed. Dealing effectively with transnational terror groups that operate with impunity across borders requires an international operation with the full cooperation of allies and partners in Europe and Asia.

This is not "mission impossible." In 1993, the United States was able to get all of the former members of the Warsaw Pact to join up with NATO in forming the Partnership for Peace to cooperate in peacekeeping operations. In 1994, the United States with the full cooperation of Russia was able to negotiate an agreement by which all nuclear weapons were removed from Uzbekistan, Belarus and Kazakhstan and by which substantial improvements were made in the security of nuclear weapons in Russia. In 1995, the United States was able to get an agreement under which NATO took responsibility for the peacekeeping operations in Bosnia, an operation that was believed at the time to be as dangerous and filled with religious and sectarian strife as Iraq today, and it was able to get dozens of non-NATO nations -- notably including Russia -- to join it in that operation.

Securing Russian cooperation required listening to Russian views and making accommodations wherever possible. As U.S. defense secretary, I had to meet with my Russian counterpart four different times before I came to understand how to structure the command in Bosnia in a way acceptable to both Russians and NATO. The general lesson from this example, which is still applicable today, was best expressed by Winston Churchill, who observed during World War II, "The problem with allies is they sometimes have ideas of their own." But in reflecting on that problem, he also said, "The only thing worse than fighting a war with allies is trying to fight a war without allies."

What lessons can we learn from Churchill today? Had the Bush administration understood better the dangers of the post-conflict phase, surely it would have worked harder to get the support of those countries before invading Iraq. In any event, after the war it would have reached out to them and tried to achieve an accommodation that would have allowed their support during the reconstruction phase.

Instead, the administration took the position that any nation that was not with the United States during the war would not have a role in the reconstruction. To compound the problem, the United States did not seek meaningful assistance from the United Nations. Today, in the light of the difficulties experienced in restoring security in Iraq, the administration is reaching out to the United Nations and requesting that it play a major role in the political reconstitution of Iraq, but it is still not working effectively with the governments of France, Germany and Russia.

Just as the United States erred in believing that it did not need more international support in Iraq, so did the Russian government err in believing that it did not need more international support as it reconstituted its government after the Soviet era. The Putin administration believed -- correctly -- that it could turn around the Russian economy without significant assistance from other countries, and it believed that it could deal most effectively with its terrorist threat without interference from other countries. It also apparently believed that moving toward a level of democracy conflicted with the controls necessary for economic recovery and for fighting its terror war. So today we see a Russia that has enjoyed a healthy 7 percent growth rate each of these past five years, but has stopped -- indeed reversed -- its move towards becoming a liberal democracy. This reversal over the long term will have profoundly negative consequences for the Russian economy and for the Russian people, and unquestionably it is setting Russia on a course that will alienate it both from the United States and the European Union.

Both the Bush administration and the Putin administration have apparently made the decision that they can achieve their goals without broad international support. Both governments have erred in that judgment. But it is not too late to correct the judgment, and I fervently hope that both of governments will do so. The most important step in that process is reviving cooperation between the United States and Russia.