President Obama to address Air Force grads amid uncertainty on US role

President Barack Obama will give his final commencement speech to U.S. military members coming of age amid fresh global threats that seem to be pulling the U.S. back into conflicts with uncertain ends.

Obama's address on Thursday at the U.S. Air Force Academy in Colorado Springs comes as the president weighs whether to once again increase the number of troops he'll leave in Afghanistan. In Iraq, U.S. troop levels have gradually crept back up, with special forces also dispatched to Syria and Libya. Concerns about Russia and China have spurred calls for a more aggressive military posture in eastern Europe and Asia.

White House officials said Obama planned to discuss security challenges facing the U.S. and the role the next generation of service members will play in protecting the country.