Los Angeles — US Senator Russ Feingold, D-Wisconsin, will turn up the volume on his challenge to the Bush White House’s failed approach to national security when he delivers a high-profile address Tuesday in this West Coast city.

The speech on national security, which will be delivered at LA’s prestigious Town Hall forum, comes on the heels of Feingold’s announcement that he will press for an Iraq “exit strategy” that would see US troops withdrawn from that country by December 2006. With his willingness to discuss a specific timelime for withdrawal, Feingold says, he is “breaking the taboo” that has stymied honest debate about the US mission in the Middle East and the point at which it can be declared complete.

The maverick senator is also drawing attention to a potential–if still decidely uphill–run for the 2008 Democratic presidential nomination as a progressive alternative to prowar Democrats such as Hillary Clinton and Evan Bayh.

Predictably, Feingold’s decision to endorse a timeline has drawn criticism from those who believe that the only way to “support the troops” and “keep America safe” is to maintain an open-ended occupation of Iraq–no matter how deadly it is for Americans and Iraqis, no matter how unstable it makes Iraq, no matter how much it does to stir resentment toward the United States.

The Bush White House dismissed Feingold’s plan with a predictable claim that it “would also send the wrong message to our troops. We are serious about completing the mission, and they need to know that they have our full support. And it would send the wrong message to the enemy, who, as the President has said many times, would just then have to wait us out.”

Vice President Dick Cheney chimed in as well, declaring that “Iraq is a critical front in the war on terror, and victory there is critical to the future security of the US and other free nations.”

Of course, Cheney was the visionary who announced on the eve of the invasion of Iraq that US troops would be “greeted as liberators.” And the Bush White House is the operation that decked the President out in flight-suit drag for a “Mission Accomplished” photo opportunity at precisely the point when the occupation of Iraq was starting to go awry. So their credibility is shot.

But that does not mean that Americans will casually endorse Feingold’s timeline.

While polls suggest that the citzenry is exceptionally ill-at-ease with Bush’s handling of the war–almost two-thirds of those polled now disagree with his approach–they need to hear more about how critics of the war would:

A) Get US troops out of Iraq, leaving a complete disaster behind, and

B) Offer a sounder approach to the national-security concerns that White House political czar Karl Rove has so ably exploited since September 11, 2001.

That will be Feingold’s challenge in Los Angeles.

So far, no Democrat who is seriously pondering a 2008 presidential run has offered a coherent statement of opposition to the Bush Administration’s misguided strategies. Senators Clinton of New York, Bayh of Indiana and Joe Biden of Delaware are all strong supporters of the war and of the Bush Administration’s general approach, while former North Carolina Senator John Edwards has sought to straddle the issues in much the same way that his running-mate on the 2004 Democratic ticket, Massachusetts Senator John Kerry, has.

If Feingold can strike the proper balance between sanity and security–grounding his push for a withdrawal timeline and a more thoughtful foreign policy in a clear commitment to do a better job of funding homeland security and developing the nation’s intelligence-gathering and international-policing capacities–he could emerge as a serious contender for the 2008 presidential nomination. At the least, he ought to be able to force the debate that must occur prior to the 2008 election onto the higher ground that Clinton, Kerry and other prominent Democrats have so far been unable or unwilling to occupy.