They know it, and they use this to put people on the defensive immediately...when there is no tangible argument, the race card is played. The best response (as suggested in article link I posted) is to not cower and get beaten down when this charge is leveled. It's a term with a floating definition, to whatever situation liberals feel it's best used to support their ideology (like a policy disagreement); instead say sure according to you I'm a racist; fine...but you may be a bigot. Bigot is a clearly defined word...there's no ambiguity.