Michael Barone explores one cause of the enthusiasm gap between Democrats and Republicans in his latest column for the Washington Examiner:

So why are Democrats less enthusiastic? And why has “the progressive donor base,” as Democratic consultant Jim Jordans reports, “stopped writing checks”?

I don’t think it’s just because the economy remains sour or that President Obama failed to jam a public option in the health care bill.

I find a more convincing explanation in an offhand phrase in a subordinate clause in a brief article by Adam Serwer of the Center for American Progress on the Washington Post’s opinion pages. “There’s no question,” Serwer writes, defying anyone to disagree, “that Obama has completely reversed on his promises to roll back Bush-era national security policies.”

For it is not economics but foreign policy that has motivated the left half of the Democratic Party over the last decade.

When Howard Dean’s supporters were declaring that they wanted to “take our country back” in 2003 and 2004, they weren’t talking about repealing the Bush tax cuts. They were talking about withdrawing U.S. troops from Iraq and taking a more conciliatory and respectful stance to the leaders of Old Europe and revolutionary Iran.

Similarly, Obama’s refusal in 2007 and 2008 to admit that there was even a smidgen of success to George W. Bush’s surge strategy in Iraq — even today he will only hint that the surge worked — cannot be chalked up to an intellectual incapacity to assimilate the facts.

It can only be explained as an unwillingness to rile the base of the Democratic Party whose concerns, as we know from Bob Woodward’s account of the president’s conduct of deliberations over what to do in Afghanistan, are never far from his mind.

Nevertheless, he has left these Democrats disappointed.