By the last firework of the Democratic convention, Obama's transformation was complete. He had systemically taken the advice of every cynical, hard-edged Democratic political consultant. Get rid of the airy, cerebral rhetoric. Pitch your message to the focus groups, not the historians. Go for the old man's jugular.

In the process, opportunities were lost. Obama said nothing interesting about race in America, at a moment when that might have been expected. He made no serious outreach to religious conservatives, something that now seems more like a ploy than a project. He offered no creative policy proposals that might transcend partisan divisions. In fact, his message ran with perfect smoothness along old partisan grooves. That is genuinely disappointing. A Democrat who wins in this fashion will be unable to rein in the inevitable excesses of the Democratic Congress. And the inevitable counter-reaction of Republicans will leave Washington, once again, a World War I battlefield of trenches and grudges.

Some illusions have also been lost. For many Americans, the exciting young candidate who won the Iowa caucuses had the promise of being a new kind of politician entirely -- better than and different from the political norm of bitterness and calculation. Those hopes now seem -- in the words of a famous Democrat -- like a "fairy tale." In this convention, Obama "matured" into the spitting image of the typical Democratic politician. And this raises a question about Obama himself. Between Iowa and Denver there is little consistency except talent and ambition. Is there anything more to this candidate than talent and ambition?

It is the conventional wisdom that this transformation is politically brilliant: In an election year of massive voter discontent, a Democrat who sounds like a Democrat will surely win.

That may be correct. But Obama seems determined to test the theory in full. The Democratic ticket consists of two of the most ideological liberals in the United States Senate. It includes no reasonable governor, no candidate with Southern roots, no member with a military background (for the first time in decades). And now it offers the purest message of partisan aggression and class resentment.

Let the depressing battle begin.