This book takes up the weightiest problems of public affairs. How should we evaluate our leaders? How do ideas of the common good influence policy? Not surprisingly, these questions prove too difficult for the author, an associate professor of political science at the University of Wisconsin-Oshkosh, to answer credibly. But David Siemers' careful framework of inquiry indicates where we stand on these issues.

Presidents and Political Thought argues plausibly that all national leaders have an interest, implicit or explicit, in political ideas. Siemers excavates the political theories with which officials came to the presidency, to see how the theories affected the decision-making of the politicians. Finally, he wants to investigate the nature of the decisions to learn how they carried forward political justice.

We have six case studies. The author starts with John Adams, Jefferson, and Madison. The Founders, almost to a man, self-consciously read political theory and in some measure saw themselves as implementing it. For his second three cases, Siemers takes Woodrow Wilson, Franklin Roosevelt, and Bill Clinton. Siemers makes the same sort of exploration, although these presidents conducted themselves at a somewhat lower theoretical level. But, I feel, we have here a bump in the road that betokens trouble down the line. Siemers wants presidents at least minimally conversant with concepts of politics. Easy enough with Wilson the academic and Clinton the policy wonk. Roosevelt constitutes another case entirely, especially given Siemers' explanation that Lincoln is ruled out because he never articulated his political philosophy. Lincoln thought as deeply about political life as anyone in human history; FDR notoriously lacked self-consciousness. Wisdom fails when you elevate FDR as a political thinker at the expense of Lincoln.

Siemers only cautiously draws conclusions from his case studies. Sensible qualifications and various sorts of strategic hedging fill the book. He has a lot of caveats. Personality plays a big role in how political philosophy operates. We often just estimate the shape of theory, an abstract enterprise, through actions. Presidents sometimes call on heavy-weight thinkers for window dressing. Many times what gets done has its origins in something other than ideas. Compromise may take place because of force of circumstance rather than because of any sort of pragmatist philosophy.

Siemers' thesis most transparently emerges when he directs us in his preface to "What we really should know about Barack Obama." While these eight pages specifically pertain to the new president, Siemers notes that they also apply to any candidates for the job during a presidential electoral campaign. We should find out what theories the man has carried with him to the White House, what books in the field he has mastered. If he hasn't any ideas about political theory, we should ask him why he doesn't have any, and he should disclose to us why political philosophy remains unimportant to him.

I found something schoolmarmish about this preface. But it does let us fairly draw the inference that Siemers wants to make a minimal, hopeful generalization. Political theorizing, as unequivocal as possible, gives us—or our leaders—at least a chance of a little leg up. Overall, as I will put it for Siemers, political theory positively relates to presidential leadership. The more concerned the president for political philosophy, the better off that politician is liable to be, and the better off his policies and the voters.

To support this view Siemers looks for an empirical correlation between presidential greatness and some pursuit of political thought. So, for example, he tries to fathom the correspondence between his political-theorizing presidents and the rankings of presidents that put the men in a graded order. Many inventories exist of Who Are the Greatest Presidents. If we look up the ratings of his six, he informs us, matters fall short of clarity. We "might" have an advantage with theorizing presidents; theory "probably has done more good than harm." Siemers hardly delivers ringing endorsements. His assessments do show the prudence of his scholarship.

Despite the acknowledged constraints on the subject, Siemers reminds presidential hopefuls that this book has discovered matters helpful to them. In his conclusion, "Dear Mr. President," he takes up ten things that candidates need to remember about political philosophy. Theories can help you understand your potential new job. You have theories about politics, even if you do not know it. You will benefit if you bring these theories to a clearer consciousness. It will challenge you to enlighten the electorate about your theories because you will have to simplify. Choose carefully the political theorists you bring to the White House. And so on.

Political theory, says Siemers in his conclusion, will most help candidates who are least inclined to study it. He offers up a brief reading list to get them started.

Here's an example from me, not Siemers. Sarah Palin runs for the presidency in 2012. She gets religion, as it were, and bones up on political philosophy. She's given A Theory of Justice to read, the canonical volume by the famed John Rawls of Harvard University. This is one of Siemers' picks, and it blows Palin away. She explains her new views to the public. Rawls urges, she updates us, that we should decide how our polity ought to work on the assumption that we have no knowledge of our age, sex, race, education, or class position. If we do this, we can figure out the best sorts of laws to pass to make American society fairer. This sort of change in our politics-as-usual, over the long run, would improve matters at the edges.

I see two connected shortcomings with this approach. The first lies in the author's notion of what ought to be whispered into the ear of princes. This shortcoming is linked to the second: Siemers' view that such whispering would advantage our public life.

Siemers narrowly construes what should matter as political theory. It first of all means those theorists whom his six presidents spoke of: Aristotle; some Enlightenment thinkers like Montesquieu, Locke, and Adam Smith; and for more recent presidents Englishmen like Thomas Babington Macaulay and James Bryce and then (for Clinton) some university scholars such as Rawls. But this truncated catalogue does not mention other thinkers important to the presidents: Romans like Cato and Cicero for the Founding Fathers, and the 19th-century Scottish Americans significant to Wilson and Roosevelt. But even a full register of our presidents' reading hardly encompasses the realm of political theory. Siemers does not take in the Catholic tradition from Augustine to Thomas Aquinas and beyond. Germany is missing, from Kant to Fichte to Hegel to Nietzsche to Heidegger and Carl Schmitt. Of course Siemers does not reference the Left doctrines embracing Marx, Lenin, Karl Mannheim, and Michel Foucault. Nor does Siemers say anything about why all these men were disregarded.

The author acknowledges that political theory now thrives professionally. He writes that "thousands of published authors" turn out "hundreds of books and articles every year." So Siemers readily admits the subjective and personal nature of his own short bibliography for presidential aspirants. He doffs his hat to Aristotle, Locke, and Edmund Burke, authors whom his six presidents have valued. To these worthies Siemers adds the writing of Tocqueville, a speech of Lincoln's, and Martin Luther King's "Letter from a Birmingham Jail." And the book wraps up by noting that practicing politicians might incline to some contemporary theorists like Rawls. Siemers warns that presidents should delve into Machiavelli with caution because of his "cavalier attitude" toward political murder.

What do Siemers' preferences convey to us? The professor implies that presidents should read more or less sunny figures, moderates. Plato does not make the cut, even though the accessible Republic discusses the necessity of leaders lying to the people, a basic factor in American politics in the recent past. I would wrongly postulate the centrality of Machiavelli because for the last sixty years political murder has been an element of American foreign policy.

Hold this thought about Siemers' abbreviated vision of political philosophy and his penchant for gentler theorists.

The second shortcoming lies in the author's carefully crafted and alert hypothesis that political philosophy will marginally help a president. Siemers intimates that politicians at the national level have a concern for political ideas. We have a hierarchy—a few presidents like Adams and Madison deserve the title of political philosophers themselves. We should look upon others like Jefferson, Wilson, and Clinton as au courant. Some, like FDR and Lincoln, embody in their efforts, if not in their consciousness, more or less coherent political ideas. Then we have a mess of thirty or so presidents who incarnate less than cogent political assumptions.

Let's put aside this large, indigestible group, among whom we might count Martin Van Buren, James Buchanan, William McKinley, Harry Truman, and the two Bushes. They have a variety of low-level, un-thought-out, perhaps inconsistent commitments that you have to stretch into political theories. People will evaluate the ideas and the presidencies of these men as variously good or bad. The existence of this group does suggest that in the great majority of cases, you have to make a minimalist case for the relevance, positive or negative, of political philosophy. I don't believe they do much either way for Siemers' view. Forget them.

But do let us consider the presidents who have paid less explicit attention to theory than Siemers' six but who still employ some intelligible notions of politics. Let's see how these men, whom Siemers does not examine, do in the roll calls of Who Are the Greatest Presidents. Try Washington and Lincoln before the 20th century. Washington is consensually regarded as the one non-intellectual Founder, but a man with principles if not a theory. Siemers reckons, please recall, that we should not deem Lincoln a more-theorizing president. Compare these two less-theorizers to Siemers' more-theorizing presidents before the 20th century, Adams, Jefferson, and Madison. Washington and Lincoln do far better on Who Are the Greatest Presidents than Siemers' three.

Go to the 20th century. I choose as less-theorizers Theodore Roosevelt, Dwight Eisenhower, and Ronald Reagan. Each of them, I would argue, has claims to have thought about his role in office, if not to the extent that rises to reflection. Compare the rankings of TR, Ike, and Reagan to those of Wilson, Franklin Roosevelt, and Clinton. I looked at two polls and, though not by much, the less-theorizers do better. Their average rank is just over 7 on the registers of Who Are the Greatest, whereas Siemers' folks average 9. As a group, his men fall a little further down the presidential pecking order.

This sort of argument constitutes Siemers' bread and butter, and these comparisons instruct me that a little-less theory outdoes a little-more theory.

The comparisons also hint at something else. Aside from John Adams, Siemers has analyzed no president from the Federalist-Whig-Republican tradition. Both Washington and Lincoln form part of the Federalist and Whig lineage of leaders. Siemers' three 20th-century people are all Democrats. My less theory-burdened men in the 20th century belong to the Republicans.

From these sorts of comparisons we might deduce that a Republican who doesn't care much about ideas likely makes a better president. Siemers would reach such a deduction if he pursued his logic with more precision, courage, and lucidity. I would not draw the implication. Rather, I would look at the shortcoming of this whole chain of investigation.

Put together the two shortcomings: the emphasis on cheerful theory, and the reasoning that we have in theory an asset to greatness. Many political scientists have only a bland managerial vision of their area of study, a League-of-Women-Voters notion of politics. They also have a difficult time thinking of Republicans as part of the American tradition. Could these professors be Democrats with a limited grasp of political life, confusing their own partisanship with knowledge?

Bruce Kuklick teaches history at the University of Pennsylvania. He is collaborating with Emmanuel Gerard on an international history of the murder of the Congo's Patrice Lumumba.

Copyright © 2010 by the author or Christianity Today/Books & Culture magazine.
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