Railing about Afghanistan is a loser politically, but it gets liberal juices going in a way the Baucus health-care bill never will. The left is more focused on pressing President Obama not to escalate in Afghanistan than it is in convincing Congress with a real grassroots push on health care. It's in the party's DNA. Liberal Democrats are more emotionally invested in war and peace issues than in sausage-like compromise on health-care legislation. ( Click here to follow Eleanor Clift )

The outcry after the public option disappeared as expected in the Senate Finance Committee is welcome, but too little, too late. Reform advocates sat on the sidelines while a vocal minority of opponents framed the debate around government power and captured the upper hand in the polls. The trajectory is shifting now, with polls showing substantial support for a public option, but the movement is not yet enough to affect Democrats with red-state constituencies.

The White House tried to stir up grassroots support. Obama's former campaign manager, David Plouffe, sent out a stream of e-mails with the aim of keeping voters engaged, but it's much harder to get people emotionally involved on behalf of a messy compromise than it was for a history-making candidate. The key to energizing the grassroots is a clear, concise, rifle-shot message with no ambiguity. What works best is a binary equation—you're for or against us—the kind of Bush-era declaration that Obama instinctively recoils from.

The binary equation for Democrats now is Afghanistan. That's where MoveOn.org, the liberal advocacy group, is targeting its latest efforts. In an e-mail message that went out last week, it urged its 5 million members to contact the White House to "tell them we need a clear exit strategy—not tens of thousands more U.S. troops stuck in a quagmire." It's a problem for Obama that his voter base is doing grassroots mobilizing on an issue where he doesn't want to be rushed. The first of five national-security meetings was held Wednesday morning at the White House to reassess U.S. strategy in Afghanistan and determine whether more troops are needed.

Young voters are a big part of Obama's database, and if they're engaged at all in post-election politics, it's on issues of war and peace. They're the ones who have to fight the wars, and they've come of age watching a disaster unfold in Iraq. A lot of them have no health insurance, but it's not what they wake up in the morning worrying about. MoveOn is running radio ads in the home states of the three Democrats who voted against both amendments offered in the Finance Committee for a public option. But if you're Max Baucus in Montana, Kent Conrad in North Dakota, or Blanche Lincoln in Arkansas, MoveOn radio ads attacking your vote are a godsend. If it wants to have some effect on whether health reform will include a public option, MoveOn should target Republicans in states Obama carried, not Democrats in states McCain carried. McCain carried Arkansas 59 percent to 39 percent. A poll released Wednesday morning shows Lincoln trailing all four of her Republican challengers, and 67 percent opposition statewide to a public option. So attacking Lincoln from the left will probably help her, not hurt her. She can show independence from her national party. This may actually be in the Democrats' best interest, but it isn't MoveOn's intended effect.

It's hard to see how anything more than a modest fig leaf of a public option can survive the current political makeup of the Senate. Even so, if Obama and the Democrats pull off a health-care bill that curbs insurance-industry excesses and expands coverage, it will be a huge deal, even if it doesn't include a full-blown public option. If they get there without any Republicans and with 60 Democrats staying together despite their differences, the Democrats will have broken through a paralysis of government that has kept the country from facing up to a host of problems, from health care and climate change to a mounting deficit that threatens the economic health of future generations.

The last piece of major social policy that required a big investment of taxpayer dollars was the prescription-drug benefit for seniors that President Bush pushed through Congress in his first term. Bush was playing on Democratic turf in calling for an expansion of Medicare, and he had the late Sen. Ted Kennedy's backing at the outset, although Kennedy didn't vote for it in the end, calling it "a slush fund" for the insurance and pharmaceutical industries. Bush made no attempt to pay for the program, even though he was already embarked on a war he hadn't paid for. President Clinton had left a budget surplus, and while everyone could see it vanishing, concerns about big government and the deficit did not carry the political wallop they do today. The final numbers were tallied at 5:53 on a Saturday morning after the vote in the House was held open for three extra hours so Republican leaders could corral enough members.

Bush's victory on Medicare owed more to Tom DeLay's arm-twisting than a sustained presidential effort like the one Obama has engaged in since taking office. Much of the current battle is about politics and ideology, not health care, with the public option a moving target. Its fate has been in the balance from the start, and now its outcome has been sealed by lawmakers impervious to liberals they don't listen to on health care—or on Afghanistan, for that matter.

Eleanor Clift is also the author of Two Weeks of Life: A Memoir of Love, Death, and Politics and Woman, Child for Sale: The New Slave Trade in the 21st Century .

© 2009