Madonna caused a minimal stir by sniping at Lady Gaga, referencing her during a concert and adding, āImitation is the sincerest form of flattery.ā At Chicagoās United Center, the first of two concerts there this week, Madonna again slipped the chorus of Gagaās āBorn This Wayā into the bridge of her own āExpress Yourselfā ā i tās a seamless match, for sure ā but let it go without comment. Well, almost. She shouted a bit from āSheās Not Meā at the end. It seems like pretty catty paranoia from the indisputable queen of pop, as if the Material Girl ā a 1 percenter if ever there were ā has adopted the Republicansā new slogan (āWe built it!ā) and its false sense of rugged individualism. Madonna broke ground for women in pop during the ā80s and easily can justify her worldwide love, but her success is a pastiche quilt, a smart synthesis of the best of the best. Wednesdayās show only lengthened the long list of film and mu...