RICO is about holding leaders responsible for the crimes of their organizations. That, in itself, makes sense (further, I recall courts being resistant to using RICO against "upstanding" but essentially criminal operations,sadly). As far as I can tell, the act doesn't extend the definitions of crimes or call for any specific enforcement whereas the Patriot does this in spades, as far as I can tell.
I can't vouch for the accuracy of this report (was a quick google search; PATRIOT was passed at a point in time where not everything was quite so webbified), but I recall the lawmakers who crafted PATRIOT used RICO as a starting point ("precedence") for the most controversial provisions. There are surely more authoritative resources out there.
"Some of the more controversial provisions of The Patriot Act were largely inspired by the RICO act, which restricted some elements of due process for individuals involved in organized crime, racketeering, and drug trafficking. The Patriot Act essentially extended the restrictions to those involved in terrorism."
one of my friends from kindergarten -> high school was Gore Vidal's last personal assistant. I hang out with him about twice a year (including this coming weekend), last year we had a long conversation about Gore... He gave me a manuscript he was writing about his time with Gore (and other things). I devoured it in 7 hours. Three days later, Gore died.