NASCAR, long a symbol of Southern heritage, has become an unlikely battleground in the debate over whether the Confederate battle flag still has a place in America.

Stock-car racing has always rewarded competitors who push themselves and their cars to the very limit - but not beyond. And with 40 cars racing at nearly 200 mph, nose-to-tail and door-to-door, everyone in the sport lives with the knowledge that one wrong move can have serious, sometimes tragic, consequences.