The Magic of the VA

Bruce McQuain says that the problems at Walter Reed prove that the VA isn't so hot.  Ezra Klein snaps back :

Walter Reed is an army hospital, not a veteran's hospital. The two systems have nothing to do with one another. That's why the problems at Walter Reed led to the resignation of the Secretary of the Army and not the Secretary of Veterans Affairs.

Ezra wins on points.  But here's the thing:  Army hospitals have all the advantages that single-payer advocates love about the VA.  They're unified.  There's no profit incentive--indeed, the doctors are on quite low salaries.  They have great incentives for preventive care.  They certainly don't have any profit motive to provide bad care.  So why did Walter Reed suck?  And what guarantees that the VA is the system we'll follow, rather than the multiple other dysfunctional government systems everyone hates?