The US military has hit as many as 17 separate targets connected to an al-Qaeda cell in Syria known as the Khorasan group.
US intelligence analysts are uncertain about whether the attacks have considerably reduced the group's capabilities.
However, US officials agree that the air attacks have forced the militants into hiding and made their use of cellphones, email or other modern communications extremely risky.
But there is some disagreement about how much the airstrikes have destabilized the group's ability to pose an impending threat.
The Khorasan group consists of veteran al-Qaeda operatives within the Nusra Front, the Syrian al-Qaeda affiliate fighting the government of President Bashar Assad.