Way back in June, Sen. Barack "middle name not permitted to be mentioned" Obama campaigned on the theme of "Change We Can Believe In." Now, several days later, his theme should be "Change We Can't Keep Up With." Apparently, the change he was calling for was not for Washington politics, but for his primary campaign positions. Abortion, gun control, capital punishment, FISA laws, the status of Jerusalem, faith-based federal programs, public financing of his campaign, welfare, NAFTA and free trade, and his commitment to the Rev. Jeremiah Wright and his Trinity Church all have fallen to reconsideration, rephrasing, changed rhetorical modulation, and other semantic miracles.

His Iraq position is currently in the process of glissading from anti to pro, so we will have to wait for a while before saying he actually has changed it. To be precise, to stay in my dance metaphor, Obama's move may not be a glissade so much as a fouétte. Centralhome.com's "Dance Dictionary" defines a fouétte as "a turning step, usually done in a series, in which the working leg whips out to the side in and then into the knee as the dancer turns on the supporting leg, rising onto the point at each revolution." I like to be precise in describing Sen. Obama because, while informal, he is a stickler when it comes to such matters.

As a conservative, of course, I like all his changed views except for the fact that he doesn't believe his current iteration of principle any more than he believed his previous iteration. Which brings us, as it always does in such circumstances, to America's greatest fraud sniffer, H.L. Mencken. He defined a demagogue as "one who preaches doctrines he knows to be untrue to men he knows to be idiots." It is not surprising that the youth is particularly enchanted by the senator from Illinois. Being young, they are inexperienced in the ways of the world.

I offer to our youth the cautionary tale of Ludwig van Beethoven when he was in his early 30s. He originally called his "Eroica" symphony the "Bonaparte" symphony as a tribute to Napoleon Bonaparte, then the heroic French consul who had begun to reform Europe radically after gaining military victories over various monarchically ruled countries. But Beethoven became disillusioned when, in 1804, Napoleon crowned himself emperor. Beethoven then renamed the symphony the "Eroica" because he refused to dedicate one of his great compositions to the man he now considered a "tyrant."

Like the young Beethoven, today's youth has not seen a truly gifted demagogue perform at the national level. Those of us who have kicked around for a while have seen such things and are not so easily impressed. We know that a demagogue need not have a black mustache or other outward signs of malevolence. He might even be tall, smartly tailored, and imperially slim, with a winning ironic way about him.

The art of being a demagogue is to appear to be an idealist. From Napoleon to even George Wallace, demagogues rise to vast popularity with the image of crusading idealists.

Napoleon rose to almost universal admiration as a champion of enlightenment principles. That is what gained him the early support of Beethoven and so many other liberal, educated youths of his time.

George Wallace's bizarre political history was that initially he was not anti-black, but he lost an election with those values. So he decided never to be seen as tolerant again. Thus, he rose to fame as an anti-black demagogue -- returning to his old tolerance only at the end of his career when tolerance was, once again, a vote-getter. But for his electorate in his time, being anti-black was the idealistic, uncompromising vision (not buckling under to Washington pointy-headed liberals).

So the art of being a demagogue is not limited to any particular issue set. It can be enlightenment reform, anti-black bigotry or anything in between. Each in its moment appealed to the youth of its time as idealistic.

Rather, the telltale trait of a demagogue is his irrationally dilated ego. Thus, the demagogue eventually, inevitably, sheds his proclaimed ideals for his personal advancement. The genuine hero is prepared to shed his personal advancement for his ideals. Sen. John McCain, for example, stuck with his support of the Iraq war even when we were losing, even if it cost him the election. How quaint. Just like an old man to stand by his principles.

So Napoleon, who condemned the ancient regime for its tyranny, eventually shed his republican principles for his own tyranny.

Of course, most American demagogues are not so expansive in their often-evil entreaties as the foregoing. Americans, being a practical people, are not susceptible to extreme ideas. So most American demagogues simply offer up whatever predilection is current.

Currently, young Americans are in a cynically practical mood stylistically and a greenish, liberal mood substantively. So Obama's constant policy adjustments tend to be admired for their alleged deftness rather than condemned for their obvious cynicism, while his liberal primary positions are presumed to be sincere -- the shifts being carried out just to trick the foolish old people who wouldn't vote for such an obvious liberal.

I leave America's voting-age children with this advice from an old poker player: When you are invited to a new poker game and look around the table for the pigeon but can't spot him, you're the pigeon.