In US Courts, the DMCA has been ruled to override the “fair use” clause in every case that has arisen and ruled upon since the DMCA was enacted. No exceptions. The “fair use” clause is a very specific exception in the first place, and software often have click through licensing that nulls it, amoung other things.
Of course, if you crack a game for yourself and don’t tell anyone nor distribute it, how would anyone find out that you broke the law?