“When you bring an act into this town, you want to bring it in heavy. Don’t waste any time with cheap shucks and misdemeanors. Go straight for the jugular. Get right into felonies.”

It’s been more than a half-century since Hunter S. Thompson went in search of the American dream on his drug-addled, off-the-rails road trip to Las Vegas.

His 1971 book, “Fear and Loathing in Las Vegas,” became an essential read for generations of teenagers who were just starting to question the world and came to define the desert gambling mecca. The book also gave birth to a new literary form, gonzo journalism, in which the reporter was a leading character — in this case a pill-popping, pot-smoking, tequila-swilling, acid-dropping “dope fiend” plunging headlong into the story.

The most enduring achievement of Mr. Thompson’s rich portfolio from the late 1960s and into the ’70s may well be how he — despite the drugs or because of them — so aptly distilled what was happening in the United States, as the disillusionment from the failures of a counterculture movement had taken hold like an iron glove around the throat.