Touring continued throughout 1970, but the group's only new recording that year was the single "Mexico" b/w "Have You Seen the Saucers?". Slick's "Mexico" was an attack on President Richard Nixon's Operation Intercept, which had been implemented to curtail the flow of marijuana into the United States. "Have You Seen the Saucers" marked the beginning of the science fiction themes that Kantner explored in much of his subsequent work, including "Blows Against the Empire," his first solo album. Released in November 1970 and credited to "Paul Kantner/Jefferson Starship," this prototypical iteration of Jefferson Starship (alternatively known as the Planet Earth Rock and Roll Orchestra) included David Crosby and Graham Nash; Grateful Dead members Jerry Garcia, Bill Kreutzmann, and Mickey Hart; session luminary Harvey Brooks; David Freiberg; and Slick, Covington and Casady. "Blows Against the Empire" peaked at No. 20 in the United States and was the first rock album nominated for the Hugo Award.