I'm a disabled veteran. Can I travel with a power or wheelchair?

Assuming you are eligible then the normal process for determining Space-A travel is followed.

According to DOD4515.13r Para 3.1.b (22 January 2016), all disabled passengers are allowed onto the aircraft and Passenger service personnel and aircraft crewmembers will provide assistance in boarding, seating, and deplaning a disabled passenger. The chief of the passenger travel section or the aircraft CDR may disapprove transportation if there is an unacceptable risk to the safety or health of the disabled passenger, other passengers, or crew, or if operational necessity, equipment, or manpower limitations preclude accepting a disabled passenger, service animal, or mobility assistance device. The aircraft Commander is the final approval authority on all matters relating to flight safety.