There may not be a tougher gig in the American orchestral scene at the moment than music director of the St. Louis Symphony Orchestra. And yet somehow, David Robertson, the young American conductor better known in Europe than in his home country, has already begun to transform the SLSO’s fortunes in only a few months on the job. “By opening night, he had already motivated the most miserable musicians in any major American orchestra (at least to hear them publicly complain); turned on teenagers as well as dowagers; and begun reaching deep into a racially divided community.”