Of course it is. It is rear wheel drive with a longitudinally mounted engine. Excellent power to weight ratio and a perfect transmission if the manual is purchased. There are race series for it and many owners autocross it. It's totally tossable.

I had one and loved driving it hard. My GTI is more powerful though it is front wheel drive and understeers terribly at the limit.

A Mazda Miata is absolutely a sports car.