Her words were emphatic: "Barack Obama is my candidate and he must be our next president." Hillary Clinton's endorsement was unambiguous and she held nothing back. She attacked John McCain with gusto and purpose and made the case for a Democratic victory splendidly and with passion and commitment.

She did such a good job, in fact, that when she left the podium and the cheering rose to a crescendo, everybody in the hall was asking the same question: Why didn't Obama pick her for vice president?

The men and women who watched Hillary - but especially the women - had to ask why. Why was she dropped from even consideration as vice president and passed over for a warmed over political hack?

Why is her voice not part of the ticket? Why was she not even vetted?

To be clear, we think that Obama had ample reason not to pick her. If he had, he'd have been stuck carrying her baggage and Bill's for the entire campaign. Could Obama have explained why Bill won't release the names of his library's donors? Could he have explained why Hillary-linked lobbyists battled to shield the Emir of Dubai from legal liability for kidnapping and enslaving children to race camels?

How could the candidate who ran against lobbyists have explained why he added the candidate of the lobbyists to his ticket?

Obama was wise not to put himself in that position. But it wasn't Hillary's negatives on display last night but her virtues -idealism, passion and vision.

It was Hillary at her best. Her sarcastic sallies against McCain provided the only good rhetoric of this so-far boring and flat convention. She brought the crowd to its feet.

Clinton's speech set forth an implied challenge to Joe Biden to equal her performance. People will compare him to her - and likely see the candidate Obama chose as inferior to the one he spurned. Biden will come across as a standard politician running against the heroine of millions of women.

With Hillary Clinton, Barack Obama could've made history - but chose not to do so. He hogged history. So her speech will likely produce no gain for him, but lay the basis for a lasting resentment at his failure to select her.

Obama is tied with McCain because he can't win the votes of women, especially older women. Last night made his a lot harder.