A climate of intolerance? An ugly mood at the McCain/Palin rallies? Ever alert to the brownshirt menace, liberals read press reports from Ohio and Wisconsin with a frisson. So where have they been these past few months? Try going into a typical progressive household to make an argument against Obama and for a Nader vote. A couple of lifelong radical friends of mine whisper to me that in their homes and workplaces they’ve given up straight talk about Obama altogether and feel free to talk, sotto voce, only in public parks.

In these last days I’ve been scraping around, trying to muster a single positive reason to encourage a vote for Obama. Please note my accent on the positive, since the candidate himself has couched his appeal in this idiom. Why vote for Obama, as opposed to against the Palin-Wurzelbacher ticket?

Obama invokes change. Yet never has the dead hand of the past had a "reform" candidate so firmly by the windpipe. Is it possible to confront America’s problems without talking about the arms budget, now entirely out of control? The Pentagon is spending more than at any point since the end of World War II. In "real dollars" the $635 billion appropriated in fiscal 2007 is 5 percent above the previous all-time high, reached in 1952. Depending on how you count them, the Empire has somewhere between 700 and 1,000 overseas bases. Obama wants to enlarge the armed services by 90,000. He pledges to escalate the US war in Afghanistan; to attack Pakistan’s sovereign territory if it obstructs any unilateral US mission to kill Osama bin Laden; and to wage a war against terror in a hundred countries, creating for this purpose a new international intelligence and law enforcement "infrastructure" to take down terrorist networks. A fresh start? Where does this differ from Bush’s commitment to Congress on September 20, 2001, to an ongoing "war on terror" against "every terrorist group of global reach" and "any nation that continues to harbor or support terrorism"?

Obama’s liberal defenders comfort themselves with the thought that "he had to say that to get elected." He didn’t. After eight years of Bush, Americans are receptive to reassessing America’s imperial role. Obama has shunned this opportunity. If elected he will be prisoner of his promise that on his watch Afghanistan will not be lost, nor the white man’s burden shirked.

Whatever drawdown of troops in Iraq that does take place in the event of Obama’s victory will be a brief hiccup amid the blare and thunder of fresh "resolve." In the event of Obama’s victory, the most immediate consequence overseas will most likely be brusque imperial reassertion. Already Joe Biden, the shopworn poster boy for Israeli intransigence and cold war hysteria, is yelping stridently about the new administration’s "mettle" being tested in the first six months by the Russians and their surrogates.

After eight years of unrelenting assault on constitutional liberties by Bush and Cheney, public and judicial enthusiasm for tyranny has waned. Obama has preferred to stand with Bush and Cheney. In February, seeking a liberal profile in the primaries, Obama stood against warrantless wiretapping. His support for liberty did not survive its second trimester; he aborted it with a vote for warrantless wiretapping. The man who voted to reaffirm the Patriot Act declared that "the ability to monitor and track individuals who want to attack the United States is a vital counterterrorism tool."

Every politician, good or bad, is an ambitious opportunist. But beneath this topsoil, the ones who make a constructive dent on history have some bedrock of consistency, of fidelity to some central idea. In Obama’s case, this "idea" is the ultimate distillation of identity politics: the idea of his blackness. Those who claim that if he were white he would be cantering effortlessly into the White House do not understand that without his most salient physical characteristic Obama would be seen as a second-tier senator with unimpressive credentials. As a political organizer of his own advancement, Obama is a wonder. But I have yet to identify a single uplifting intention to which he has remained constant if it has presented the slightest risk to his advancement. Summoning all the optimism at my disposal, I suppose we could say he has not yet had occasion to offend two important constituencies and adjust his relatively decent stances on immigration and labor-law reform. Public funding of his campaign? A commitment made becomes a commitment betrayed, just as on warrantless eavesdropping. His campaign treasury is now a vast hogswallow that, if it had been amassed by a Republican, would be the topic of thunderous liberal complaint.

In substantive terms Obama’s run has been the negation of almost every decent progressive principle, a negation achieved with scarcely a bleat of protest from the progressives seeking to hold him to account. The Michael Moores stay silent. Abroad, Obama stands for imperial renaissance. He has groveled before the Israel lobby and pandered to the sourest reflexes of the cold war era. At home he has crooked the knee to bankers and Wall Street, to the oil companies, the coal companies, the nuclear lobby, the big agricultural combines. He has been fearless in offending progressives, constant in appeasing the powerful.

So no, this is not an exciting or liberating moment in America’s politics such as was possible after the Bush years. If you want a memento of what could be exciting, I suggest you go to the website of the Nader-Gonzalez campaign and read its platform, particularly on popular participation and initiative. Or read the portions of Libertarian Bob Barr’s platform on foreign policy and constitutional rights. Cynthia McKinney is now making nutty claims about 5,000 post-Katrina executions; otherwise I’d include her.

Do you really want to be on the same side as Alan Dershowitz, Colin Powell and Christopher Hitchens?