Interesting post from Rorate Caeli (link below). It talks about the two different periods of Modernism that we have faced, starting during or immediately after Vatican II. First there was the dissent of the Modernists against Church teachings, and the way it spread into the Church. The second phase is when Modernism came to power, and whether it is good, or lawful, to resist a Modernist superior.
For information on Modernism, I suggest the Encyclical Pascendi Dominici Gregis from Saint Pius X.