NEAR TULUL AL-BAQ, Iraq  President Obama has set an August deadline for the end of the combat mission in Iraq. Here at this makeshift desert camp in the insurgent badlands of northern Iraq, a mission is under way that is not going to stop then: American soldiers hunting terrorists and covertly watching an Iraqi checkpoint staffed by police officers whom the soldiers say they do not trust.

“They’re not checking anybody, and they’re wondering why I.E.D.’s are getting in to town,” said Staff Sgt. Kelly E. Young, 39, from Albertville, Ala., as he watched the major roadway that connects Baghdad with Mosul, regarded as the country’s most dangerous city. He referred to improvised explosive devices, the military term for homemade bombs.

The August deadline might be seen back home as a milestone in the fulfillment of President Obama’s promise to end the war in Iraq, but here it is more complex. American soldiers still find and kill enemy fighters, on their own and in partnership with Iraqi security forces, and will continue to do so after the official end of combat operations. More Americans are certain to die, if significantly fewer than in the height of fighting here.

The withdrawal, which will reduce the number of American troops to 50,000  from 112,000 earlier this year and close to 165,000 at the height of the surge  is a feat of logistics that has been called the biggest movement of matériel since World War II. It is also an exercise in semantics.