If the great and glorious David Petraeus and the shiny Robert Gates are saying, "Bring the troops home," then you've defused your enemies.
Exactly. Or, for instance, which of the following had a more significant impact on public opinion: Michael Moore endorsing Barack Obama or Colin Powell endorsing Barack Obama? The Moore endorsement reinforced the base to be sure, but the Powell endorsement had significant pursuasive impact because it came from the other side.