The United States lacks the power to transform the Greater Middle East.

Almost one-and-a half billion Muslims live in many countries ─ north, south, east, and west ─ within the huge area stretching from Iraq to Pakistan. Expecting to reshape these nations is thoroughly unrealistic.

This is the first of five lessons that Andrew Bacevich imagines sharing with Barack Obama as the latter assumes the presidency next week. He judges it vital for the new president to lead the way in breaking with the myths that, since 9/11, have been shaping U.S. foreign policy.

On issues of war and peace, Bacevich, a political science professor at Boston University, has great credibility. Formerly a colonel in the U. S. Army, he served in the Vietnam War and in Germany and the Persian Gulf. Sadly, his only son Andrew, an Army lieutenant, was killed in Iraq in 2007 by an improvised explosive device.

In a recently published book, The Limits of Power: The End of American Exceptionalism, Bacevich argues that belief in the United States’s right to shape the world as it wishes is unreasonable and flies against our national interests.

Recently I heard the author deliver a sober but hard-hitting talk in which he explained his views. That talk has provided me with further fodder for my late-life skepticism about the myths that determine so many of our nation’s attitudes and policies.

The second lesson Bacevich would share with the new president is this: preventive war does not work. Moral considerations aside, to justify taking initiative in starting such a war you must satisfy two conditions.

First, the war has to be rapid, economical, and decisive; and second, the attacker has to demonstrate to other adversaries that it could repeat this assault quickly against them. The U.S. has failed to meet these conditions in the Iraq War.

Using blunt language on this topic, Bacevich concludes: “Preventive war is a dumb idea.”

A third lesson for President Obama to consider: The limits of American military power have been revealed. The colonel does not deny that our military is incomparably the best in the world. If we can get adversaries to fight on our terms, he says, we’ve got them beaten.

In a protracted unconventional war, however, we don’t have enough soldiers. And in such a conflict, we don’t have sufficient domestic popular support. So, despite towering investments, our power remains limited.

A fourth lesson: Our capacity to get other nations involved is limited. The so-called “coalition of the willing” proved no adequate substitute for long-standing alliances. Other nations, it turns out, will offer their support for U.S. leadership only if it’s in their interest to do so.

A final lesson: Even when friendly nations offer us their support, they don’t have much to offer. NATO, for example, is no longer the force it once was, when it served as Europe’s bastion of defense against the Soviet Union. The European nations are not interested in spending their resources on this kind of effort.

From these lessons, Bacevich draws several conclusions, including one that concerns the global war on terrorism. It cannot be judged an effective strategy. Instead, it squanders American power and should be scrapped. We need to define our task in different terms.

This kind of analysis, in my judgment, can help sort out true and false. Coming from a man with significant military experience combined with scholarly achievement, it can serve to undermine illusions about war and peace.

This fall, to my great pleasure, I became acquainted with a young veteran of three tours of duty in the Iraq War. This former Marine officer is well educated and has given much thought to his experience.

When I sent him an email asking about his view of the war’s morality, he replied thoughtfully and frankly. “Everyone in the military believed the situation was far worse than it turned out to be in terms of WMD and everything else,” he wrote.

This response echoes what Americans in general were led to believe. The media, by and large, accepted this rationale for the invasion, as did most other segments of our society. It was only later that people began to understand, and to discredit, this argument for beginning a war.

Though mine is a long history of skepticism about reasons for war, in later life it has become even more intense. When I see unfold on the News Hour the list of American dead in Iraq, especially the 18 and19-year olds who have hardly lived, I could weep in sorrow and anger. The terrible judgments made by national leaders that brought on such a disaster seem to me the depth of folly.

Age can give new perspectives for judging such decisions without the cloud of myth that obscures reality. As we enter upon a new era next week, my hope for our country is for us to shake loose from the false notions that do our nation such harm.

Richard Griffin