Robert Hughes writes that Richard Serra is one of Amer’ica’s three greatest sculptors. Ever. In fact, Hughes says, Serra’s new installation at Guggenheim Bilbao makes Gehry’s architecture seem pale by comparison. “Let’s come right out with it: on the basis of his installation of one old and seven new rolled steel sculptures at the Guggenheim Museum in Bilbao, we can call Richard Serra not only the best sculptor alive, but the only great one at work anywhere in the early 21st century.”