Within the past ten days Barack Obama has given two major speeches, one outlining his plan for the war in Afghanistan and today’s acceptance of his Nobel Peace Prize. The reviews are still coming in for this latest disquisition but the first effort was not well-received. As liberal pundit Kevin Drum wrote at Mother Jones:

There are two possible reasons for the speech being so unconvincing: either Obama doesn’t know how to deliver a good speech or else Obama isn’t really convinced himself. But we know the former isn’t true, don’t we?

Do we? In 2008 I was writing a book on persuasion that uses Aristotle’s framework to analyze the rhetoric of Jesus. Throughout the book I used modern examples, including contemporary politicians such as Ronald Reagan and Bill Clinton, and was eager to add a recent model of exemplary ability. Several people suggested I include an example from candidate Obama since he was being praised as one of the premier orators of our time. Surprisingly, when I asked for specific instances of his rhetorical excellence no one could think of any. After examining a number of his speeches for myself I discovered why: Despite the hype, Obama is a rather lackluster political rhetor. Indeed, if the primary purpose of political rhetoric is persuasion, then Obama’s oratorical ability is below-average.

To see why he fails we can turn to Aristotle and the three essential components he identified for effective rhetoric: pathos, logos, and ethos.

Even his most ardent supporters recognize Obama’s limitations in the use of pathos (persuading by the use of emotion). Unlike his Democratic predecessor Bill Clinton, Obama lacks the natural empathy to connect with an audience and has shown no sign of having the ability to verbally “fake it.” Also, despite his reputation for Spock-like logic, his muddled one-one-hand/on-the-other-hand, reach out to both sides approach tends to undercut his use of logos (persuading by the use of reasoning). Part of that blame lies with his speechwriters, but Obama has yet to deliver an address that would convince the unconverted.

But it is ethos—the persuasive appeal of one’s character—that is responsible for both his inflated reputation as an orator and the disillusionment and disappointment many of his supporters have after hearing him speak. Unlike logos and pathos, ethos is a property of communication that belongs not to the speaker, but to the audience. The listener, rather than the rhetor, determines whether the speaker’s ethos is high or low. Before the election, when he was the embodiment of hope and change, Obama’s supporters imbued him with a high ethotic value. Now that he is President, and making unpopular decisions based on the realities of governing, many of these same fans are finding him less persuasive.

In some ways, conservatives should be pleased by Obama’s lack of rhetorical ability. Those of us who oppose much of his domestic agenda are relieved that he can’t simply go on a speaking tour and convince large segments of the skeptical populace to support his policies. But in some ways, his failure to persuade may be detrimental to the aspirations and objectives of the nation. As the elected political leader of the United States—and the unofficial spokesman for the West—the President holds the most powerful bully pulpit in the world.

Yet in his first year in office Obama has never given a convincing speech on the world stage. It is difficult to even identify a memorable line, much less a passage that will resonate through the ages. So far, no great harm has been caused by his limitations. We may soon discover, however, the disadvantage of having a leader who combines natural charisma and a mellifluous voice with a complete lack of persuasive rhetorical ability.