The Democrats—once they took control of the House, the Senate, and the White House—said they couldn't move more aggressively on the Democratic agenda that they campaigned on and that won them three national elections in a row because, my goodness, that might cost them control of the House and the Senate. And now they're in danger of losing control of the House and the Senate anyway... and we don't have a public option or ENDA or closed Gitmo or a repealed DADT to show for it.
Good work, gang.
UPDATE: From comments...
The Dems are in danger of losing the Congress because the economy sucks, not because we don't have a public option—which was never explicitly promised by Obama.
The commenter has it right: the Dems wouldn't be in danger if the economy didn't suck so hard. But that's also irrelevant to my point. Yes, events beyond the control of the party in power can result in that party losing control. I learned this lesson as a wee child when a snowstorm undid the mayor of Chicago, a career politician with the backing of the city's all-powerful machine. Since everyone knows, or should know, that something beyond the control of the party in power—a tanking economy, a snowstorm, a sex scandal—can result in that party losing control, the party in power has to move on its stated, winning agenda. You push through your agenda while you're in charge because there's no guarantee that you'll be in charge after the next election. Majorities are fleeting. Use it because you're going to lose it.
And since everyone knows a political party is eventually going to lose its majority—there's no such thing as a permanent majority, however cautiously you govern, however much fun it is to fantasize about one—a party that jettisons its agenda to preserve its majority is guilty of political malpractice and deserves to lose.
As for Obama not making any explicit promises about the public option: bullshit.