ON FEB. 12, Joaquin Guzman Loera, aka “El Chapo,” was convicted of multiple crimes related to running the Sinaloa drug cartel, Mexico’s largest.

Thirteen days before his conviction, authorities seized enough of the synthetic opioid called fentanyl for 100 million lethal doses.

It was hidden in a truck carrying cucumbers through the Nogales port of legal entry.

On Feb. 28, authorities at the port of Newark were inspecting a container ship that had arrived from Colombia. Inside a container supposedly filled with dried fruit, they found 3,200 pounds of cocaine, worth $77 million on U.S. streets.

This was two days after Don Winslow published “The Border,” the final volume in his 1,900-page trilogy of novels (“The Power of the Dog” and “The Cartel”) about the cartels and the U.S. “war on drugs.” He could hardly have arranged a better launch for his book, which is already on best-seller lists.

His thesis is that the war on drugs resembles the Vietnam War in its futility and its collateral damage to Mexicans, more than 250,000 of whom have died and another 40,000 have disappeared, according to the Financial Times, in the past dozen years from violence associated with rivalrous cartels and law-enforcement measures.

Those endless photos of confiscated sacks of drugs do resemble old photos of dead Vietcong — body counts of replaceable bodies. El Chapo, 61, will die in a U.S. “supermax” prison, and his incarceration — he has been in custody since 2016 — will make no difference regarding drug flows.

The mayhem and sadism Winslow describes are, he says, derived from credible reports.

Wonder what the Central Americans who trek through Mexico to the U.S. border are fleeing?

Read Winslow’s description of a 10-year-old Guatemalan living off a garbage dump, alert for trucks bringing garbage from the better neighborhoods.

Winslow might be right about sinister involvements of some U.S. financial institutions in handling the cartels’ billions.

He could, however, have omitted the thinly — very thinly — disguised President Donald Trump, and his son-in-law, who knowingly uses drug cartel money to rescue himself from a bad Manhattan real estate bet.

One reason to read fiction is to avoid reading about those people.

However, the upward of $40 billion in profits made from the $150 billion U.S. market — 30 million consumers of illicit drugs — must go somewhere.

First, to Mexico, “so much cash,” Winslow says, “they don’t even count it, they weigh it.” But then where?

Every day 4,500 trucks pass, necessarily with usually minimal inspection, through three legal entry points along the U.S.-Mexico border.

Any wall would be irrelevant to interrupting drug shipments.

As is the strategy of bringing down cartel kingpins.

The New York Times reports that in 2016 and 2017, when El Chapo was in custody, “Mexican heroin production increased by 37 percent and seizures of fentanyl in places like Nogales more than doubled.”

The “supply side” attack on drugs is frustrated by, among other things, geography and the torrent of south-north commerce. The “demand side” is frustrated by declining prices (the supply-side failure) for increasingly potent products, such as fentanyl, which has passed prescription opioids and heroin in overdose deaths.

Made from chemicals, not crops, and patented almost 60 years ago, it is mixed with heroin for an extra kick — and if doses are not carefully calibrated, a lethal kick.

Says New York University’s Mark A.R. Kleiman: In 1979, a milligram of pure heroin sold for about $9 in today’s prices; today it costs less than 25 cents.

“Fifty grams of fentanyl — just over an ounce and a half — has the punch of a kilogram of heroin, and it’s way, way cheaper.” Three hundred micrograms — “roughly the weight of a grain of table salt” — can kill.

And dealers are not precise chemists.

“We have,” Kleiman says, “about 30 times as many drug dealers behind bars today as we had in 1980” but today’s dealers employ cellphones, texting, social media and home delivery. In the most recent Global Drug Survey, Kleiman says, “cocaine users around the world reported that their most recent cocaine order was delivered in less time, on average, than their most recent pizza order.”

He notes that serious cultural change has taken 50 years regarding tobacco, yet it is “still much more widely used than any of the illicit drugs except for cannabis.”

And “the fentanyls aren’t going to be the last class of purely synthetic and super-potent recreational chemicals; they’re just the first.”

Worse living through chemistry, even if it disadvantages the crop-growing cartels of Winslow’s epic.

George Will’s email address is georgewill@washpost.com.