Gen. Petraeus: Military force 'not sufficient'

US Gen. David Petraeus said Thursday that insurgents in Iraq have sought to intensify attacks during a Baghdad security crackdown, which he predicted should not be at full strength until June. But Petraeus, the new commander of US forces of Iraq, also stressed that military force is "not sufficient" to end the violence in Iraq and political talks must include some militant groups now opposing the government. "This is critical," said Petraeus, who noted that such negotiations "will determine in the long run the success of this effort."