Is a rotary wing craft capable of supersonic flight? Just what the title states.

Since the Wright brothers, aviation technology for fixed-wing craft has advanced by an order or more. Rotary wing craft on the other hand (I know little about aviation; please correct me!) have advanced significantly by way of lift capacity, and maneuverability. Yet velocity has achieved nothing like the kind of advance seen in case of fixed-wing craft.


Is a rotary wing craft capable of supersonic flight? 
How is it limited by contemporary technology?
Currently there is no rotary wing craft capable of supersonic flight. 

Combined with the forward motion through the air, the rotating blades attack the air on one side and retreat backwards on the other.  As the aircraft moves faster this poses 2 problems:


The retreating blade has a point of zero air speed, starting from the axis at hover and moving to the tip with forward speed, an effect known as P-factor.  Eventually a large portion of the blade has negative airflow (backwards to what it had when hovering) causing loss of lift control on that side (there may still be lift, but the pitch of the blade has little influence). The craft will roll (and I believe gyro forces will bring the pitch up, and the craft will recover)
The advancing blade will go supersonic, starting from the tip. Aerodynamics change.


There are ideas of new blade actuators that can change the blade for 1) reverse airspeed and 2) supersonic aerodynamics.  As you have noticed, nothing has panned out so far...