An Air Force MQ-9 Reaper unmanned aerial attack vehicle. UPI/Brian Ferguson/U.S. Air Force WASHINGTON, Feb. 5 (UPI) -- A White House spokesman said Tuesday President Obama takes the war against al-Qaida seriously, and drone strikes against the terrorist organization are legal. White House press secretary Jay Carney was responding to a U.S. Justice Department memo, made public Tuesday, that says the United States can target its own citizens with drone strikes if they have recently been involved in violent attacks. "I can just say that this president takes his responsibilities very seriously," Carney told reporters at the White House, "and first and foremost, that's his responsibility, to protect the United States and American citizens. He also takes his responsibility in conducting the war against al-Qaida as authorized by Congress in a way that is fully consistent with our Constitution and all the applicable laws. He added: "We have acknowledged ... that sometimes we use remotely piloted aircraft to conduct targeted strikes against specific al-Qaida terrorists in order to prevent attacks on the United States and to save American lives. We conduct those strikes because they are necessary to mitigate ongoing actual threats, to stop plots, prevent future attacks and, again, save American lives. These strikes are legal, they are ethical and they are wise. The U.S. government takes great care in deciding to pursue an al-Qaida terrorist, to ensure precision and to avoid loss of innocent life.