This is not a "good" book for pot sympathizers. It's about a big pot smuggling "ring" operating from mid-1970'ies to late 1980'ies. The angle is how successfully the evil pot smugglers were "brought to justice" (the author seems obsessed with the expression, never questioning any of the forms of "justice"). And about how sad it was that DEA agents were caught out as personally corrupt, and caught corrupting the cases to catch smugglers on false and bent charges.
What a pot buff can glean from this book is how a lot of pot was shipped worldwide 30 years ago. But the results are given, as we already know the pot got here - to the markets, i.e. people eager for mostly harmless fun. It still does. E.g. some 80-100.000 metric tons raw pot annually out of Morocco, amounting to only est. 60-70 % of EUropean hashish markets, which again is only est. half the EU cannabis market (EMCDDA-numbers). Despite the scale of the smuggling, the pot plots in the book were a small part of that. Though the ring's hauls and busts did influence US West Coast prices.
Written like a trad crime story tracking down perpetrators, the author misses the point about pot-use being part of an ideological struggle of materialism vs. "easy living".
If you "must have" this book, for some unfathomable reason, you can have mine. Read e.g. Howard Marks instead, learn more.