The shattered Kristol ball.(foreign policy )

TO WHOM should the next president turn for advice on foreign policy: realists or neoconservatives?

Given the disastrous results that neoconservative policies have produced since 2001, the answer seems obvious. Yet despite their repeated failures, prominent neoconservatives are now advising GOP candidate John McCain, and they remain a ubiquitous presence on op-ed pages and TV talk shows and in journals of opinion (along with their close cousins, the liberal interventionists). By contrast, realists have become an endangered species inside the Beltway and a muted voice in contemporary policy debates.

This situation would make sense if neoconservatives had proven to be reliable guides to foreign policy and if realists had been consistently wrong. But the truth is the opposite: neoconservatism has been a road map to disaster while realism's policy insights remain impressive. If the next president wants to avoid the blunders of the past eight years, he must understand why neoconservatism failed, steer clear of its dubious counsel and rediscover the virtues of realism. To see why, one need only examine the core principles and track record of each perspective.

AS THE LABEL implies, realists believe foreign policy must deal with the world as it really is, instead of relying on wishful thinking or ideological dogmas. Realism sees the international system as a competitive arena where states have to provide security for themselves. Realists know that states get into trouble if they are too trusting, but that problems also arise when states exaggerate external dangers, misjudge priorities or engage in foolish foreign adventures.

Thus, realists keep a keen eye on the balance of power and oppose squandering blood or treasure on needless military buildups or ideological crusades. They know military force is the ultimate guarantor of security, but they recognize that it is also a blunt instrument whose effects are unpredictable. Realists are therefore skeptical of grandiose plans for global social engineering and believe that force should be used only when vital interests are at stake.

Realists appreciate the power of nationalism and understand that other states usually resist outside interference and defend their own interests vigorously. Thus, realists discount the possibility that adversaries will form a tightly unified monolith and favor undermining opponents through "divide and conquer" strategies. Realists also recognize that successful diplomacy requires give-and-take and that the pursuit of U.S. interests sometimes requires cooperating with regimes whose values we find objectionable. In short, realists know that successful statecraft requires strength, cold-eyed calculation, flexibility and a keen sense of the limits of power.

Yet realists are neither moral relativists nor disinterested in values. Realists are aware that all great powers tend to think that spreading their own values will be good for others, and that this sort of hubris can lead even well-intentioned democracies into morally dubious ventures. Realists do cherish America's democratic traditions and commitment to individual liberty, but they believe these principles are best exported by the force of America's example and not by military adventures. They also know that prolonged overseas meddling is likely to trigger a hostile backlash abroad and force us to compromise freedoms at home.