Williamson's comments are not wacko and most SSPX adherents love the man for his clear reason among his other saintly qualities.
Citing the Protocols of the Elders of Zion (see also #245 there) is not "wacko"? Sorry, but that's just bizarre, especially from a Bishop.
Few of you will be surprised to learn that the September letter appealing to the women not to wear trousers caused a strong reaction, comparable only to the reaction to the Seminary letter which referred to scientific evidence that certain famous 'Holocaust gas-chambers' in Poland cannot have served as gas-chambers at all. ...Not the vile media played no doubt a large part in inflating the issue out of all proportion, in order amongst other things, whichever side won, to bring the Supreme Court into disprepute: "... it is indispensable to stir up the people's relations with their governments in all countries so as utterly to exhaust humanity with dissension, hatred, struggle, evny... so that the goyim see no other course open to them than to take refuge in our complete sovereignty in money and all else" (Pr. 10).