It was Dorothy's dog Toto, a standard bred cairn terrier, in the 1939 movie classic "The Wizard of Oz," tugging at the black curtain, who revealed the Great and Powerful Oz to be nothing more than a humbug,

"Why, you're not a wizard at all, you're just a man! And you're a very bad man for pretending to be a wizard," exclaims Dorothy.   Professor Marvel, chagrined after having been defrocked, and exhausted, unable to sustain the charade, replies apologetically, " Oh no my dear, I'm a very good man, just a very bad wizard."

President Obama, also pretending to be a wizard, was finally defrocked at his own hand by a pathetic performance in what should have been an unremarkable low profile legislative routine but which ballooned into the debt ceiling debacle. Discredited by his serial lying about default and terrifying seniors about Social Security payment suspensions, while telling bankers behind the scenes that such calamities would not happen, Obama can't lay claim to be a very good man, either.

No doubt his intrinsic ethics deficit has been inflated by an ideological stubbornness about class warfare, higher taxes and bigger government.  His poll numbers are plummeting even among fawning defenders.  He is a feckless bystander, making fools of those swept off their feet in 2008, voting with their hearts, "someplace over the rainbow" for a Tin Man without an oil can.

And now, Obama's closest allies in Congress finally admit what many of us knew all along.  Like a package constructed of sugar cane and bamboo, he's as fragile as the wicked witch, melting at the first drops of a splash of water in his face.

Two Fridays ago Obama himself acted out the dual characters of both the failed Wizard of Oz and the terrier Toto, at his hastily called late day press conference when he ordered the Speaker of the House, John Boehner, to deliver the broomstick of the wicked witch. As everybody knows by now, the broomstick would be in the form of more tax hikes, the only solution Obama has for any and all of our "double, double toil and trouble."

Such a broomstick, in lore, would be finding the holy grail, conquering evil,  the sweet fruit  borne by a knight errant.  But Obama's performance was more transparent than usual, now obvious to anyone who had been clinging to the hope that Obama would change himself, yearning for him to display, for the first time, a glimmer of presidential leadership.

Obama previously sent his knights errant , Erskine Bowles and Alan Simpson,  on the same quest for the witch's broomstick.  Of course Bowles and Simpson returned empty handed -- without Obama's singular vision for America -- more class warfare, more taxes, more redistributive spending, thus were summarily dismissed.  To his credit, despite assaults from hard core conservatives that he has been timid, Speaker Boehner rightfully refused to seek, let alone find and deliver, the witch's broomstick.

 The debt ceiling saga serves up many lessons; the most apparent is the chronic dysfunction of today's Congressional leaders, unable to muster sufficient brainpower and courage, unlike Dorothy's companions, the Scarecrow and the Lion.

A parallel lesson, just as profound and more instructional, is the sorry consequence that befalls a nation after it chooses a president based on identity politics alone, where the subject of infatuation is mere vaporware, just an imaginary figment, a momentary reflection from a wistful gaze into a crystal orb.

Obama is finished.  The election in 2012 won't be close.  The Republicans would have to nominate someone hopelessly inept and obnoxious to enable Obama's resuscitation.

Obama is sharing the exit script with Oz's onetime Wizard, vanishing as the hot air balloon ascends uncontrollably. "I can't come back. I don't know how it works."

Illustration: The Wizard of Oz, from 1900 original edition.