End game: democratic Iraq hawk Ken Pollack says our military can't stop Iran from going nuclear. And our diplomats don't have much chance either.

The Persian Puzzle: The Conflict Between Iran and America By Kenneth Pollack Random House, $26.95

As George W. Bush's second term in office begins, he faces an array of daunting foreign policy challenges, any one of which could consume his presidency entirely: 150,000 American troops fighting the insurgency in Iraq, with no end in sight; nearly 20,000 U.S. combat forces in Afghanistan; the war on terror with Osama bin Laden on the loose; North Korea's nuclear weapons program up and running; China's increasing military and economic power coupled with its efforts to expand its political influence throughout Asia and beyond; Russia's continuing backslide into authoritarianism and regional bullying; Israel's upcoming withdrawal from Gaza and a post-Ararat Palestinian leadership teetering on the brink of a full meltdown; and a U.S.-European relationship that is deeply poisoned and threatening to get worse. Meeting each of these challenges is critically important to America's national interest, and each will be difficult to manage, let alone solve.

But, as tough as all this seems, the country that should cause the most hand-wringing about our long-term security interests is Iran. The world's leading state sponsor of terrorism, Iran is a sworn enemy of the United States, and is committed to the annihilation of Israel. Iran's own Islamic revolution 26 years ago has served as a model and inspiration for Islamic extremists worldwide. This theocracy sits atop of one of the world's largest supplies of oil. It has an abysmal human rights record. It aspires to play a greater regional role, especially in Iraq. It desperately wants an independent nuclear capability--which few doubt it intends to use for weapons--and has moved closer to doing so during the past four years. And to make matters worse, Iran presents a problem that defies easy solutions--for many years, it has been for Americans one of those challenges where a policy of drift looks better than any alternative.

Despite Iran's obvious but troubling importance, it is a country that most Americans, as well as most foreign policy specialists--including this one--really know little about. That's why I'm thankful for Kenneth Pollack's important and groundbreaking new book, The Persian Puzzle. By combining detailed history with rigorous policy analysis, and writing with refreshing clarity and zip, Pollack has given us the single best book on the U.S.-Iran relationship to date.

Pollack is best known--and perhaps will forever be known--for his 2002 book on Iraq, The Threatening Storm, which famously made the case for U.S. military invasion. Many will read this new book in light of the old one, suspecting that, by opposing a full invasion of Iran, he may be trying to atone for his earlier position on Iraq. Perhaps. But Pollack tackles America's tangle with Iran on its own--in all its frustrating complexity--leaving a reader enlightened yet, given the stakes involved and the lack of attractive policy options available, also frightened.

Some historical background is necessary to understand the current struggle with Iran--especially because collective memories on both sides drive so much of the tension today. Most of Pollack's book is a very accessible survey of this story, starting from the beginning (literally) in the Ice Age, to the rise of Persia and Shia Islam , and then moving quickly through the rise and fall of Reza Shah Pahlavi, who was in many ways the founder of modern Iran. But the bulk of this history concerns U.S.-Iran relations during and after the reign of Reza Shah's son, Mohammed Reza Shah, under whose control Iran both developed and decayed, opening the door for the 1979 revolution and Ayatollah Khomeini's modern Islamist autocracy.

Pollack argues that, above all else, two events--the CIA-orchestrated 1953 coup of then-prime minister Mohammad Mosaddeq, and the 1979 takeover of the American embassy in Tehran by Islamic revolutionaries--are inextricably linked and define the U.S.-Iran relationship. Of course, this argument has been made before, and the story behind each episode has been told. But Pollack's depictions of both are worth reading closely--for his unvarnished assessments of American actions, as well as for his explanation of the implications of each event for the history that unfolded.

The 1953 Mosaddeq coup that reinstalled the Shah burned into Iran's collective psyche a simple but enduring idea: that the United States was a malevolent power determined to control Iran, and, therefore, Iran needed to develop the capacity to act independently. The 1979 embassy takeover--which Pollack describes as "an act of vengeance for the 1953 coup"--showed the Iranians and others that terrorism works, seeing the feckless U.S. response as a sign of weakness. And Americans learned the lesson that Iran was a country that should be isolated and occasionally punished, but never dealt with. Devising a solution to the Iran problem proved too difficult, and no American leader wanted to open himself to the charge of "coddling" the mullahs. As Pollack shows, from Reagan through George H.W. Bush and Clinton to President Bush today, the United States has tried to "wash our hands of the problem of Iran."

This position has never worked very well, but in today's world, it is completely untenable. As Pollack describes it, there are two clocks ticking in Iran. One is the clock of political transformation, led by reformers and Iran's youth movement, interested in deepening ties to the West. Such deepening may eventually occur, Pollack argues, but no time soon, especially since the Iranian regime has been relatively successful at pursuing a "China model," combining a sliver of openness with repression that has, for now, reduced the pressure for change.

The other clock is that of Iran's nuclear program, which is ticking faster. Less than three years after Iran admitted to the International Atomic Energy Agency that it had been secretly developing technology that could be used to build nuclear weapons, Iran has been persuaded only to freeze these programs, not end them. This is, at best, a bandage--not a serious policy to end Iraq's nuclear ambitions. Conservative estimates have Iran's nuclear weapons clock going off in the next five to 10 years; some (like the Israelis) believe it could happen much sooner.

As both clocks tick along, Washington has to do more than wish them away. "Iran is on the wrong path and marching down it quickly," Pollack argues, and the United States does not have the luxury of pursuing a "purely passive" approach.

Yet what exactly should we do? Unfortunately, Pollack does not have an easy answer. He shows that many of the policies commonly talked about--from a "Grand Bargain" to solve the conflict, to targeted airstrikes, to regime change or a full military invasion--are either unworkable or not worth the costs involved. Instead, Pollack proposes a complex approach toward Iran that would place priority on dealing with its nuclear program, while also addressing other parts of the relationship, like Iran's support for terrorism and political and economic ties to the West. He urges the use of whatever leverage America and its allies have to modify Iran's behavior, such as carrots like expanded trade and WTO membership and sticks like greater economic and political isolation. And he calls for working toward closing the loopholes in the Nuclear Nonproliferation Treaty that allows countries like Iran to get as far as they have in developing nuclear capability legally--a smart idea worth another book on its own.

Pollack's proposal reflects tough pragmatism, but he is not optimistic about success. He is careful to describe his proposal as the "least bad option," questioning whether the Iranians realty want or are capable of any deal at all. Given this, he argues that a key part of any new policy must be to rethink the containment of Iran and, ominously, to prepare for living with a nuclear Iran.

The trouble with all of this is that it demands a president and an administration prepared to get to work--and capable of working with allies--to solve the problem. So far, that is not something President Bush has shown much willingness to do. His administration has been too internally divided to do anything at all. Instead it has left it to the Europeans to handle Iran, which is an odd way to deal with such a critical threat to America's security interests. Once again, the Bush team is acting unilaterally--but rather than doing something alone, it is doing nothing alone.

This illustrates the point that many Bush critics--most recently Sen. John Kerry and former senator John Edwards during the presidential campaign--make about the costs of America's increasing isolation abroad. America doesn't pursue allies in order to win popularity contests or to make its citizens feel better. We do so in order to solve problems that cannot be solved alone. Using diplomacy, which puts us in a stronger position if we need to use force. As Pollack puts it, the decision about what to do about Iran "may be the ultimate test of America's leadership in the new era that is dawning." Such phrases have been written so often recently that they have become cliches. But if there's one conclusion to draw from Pollack's book, it is that while Iran has become one of the world's leading problems, the only way to solve this Persian puzzle is for the United States to lead the world.

Derek Chollet was foreign policy adviser to Sen. John Edwards from 2002-2004.