How did Sen. Cory Booker (D., N.J.), an Ivy League–educated Rhodes scholar with multiple degrees, miss his shot at the presidency?

With 14 words: “I have no idea what’s in a Long Island iced tea but iced tea!”

Booker dropped out of the race on Monday, following his failure to qualify for the January primary debates. But he blew his chance with this dorky comment on BuzzFeed’s “Am to DM” last February. After claiming a Long Island is mostly iced tea (FACT CHECK: the drink is a toxic mixture of rum, vodka, gin, tequila, triple sec, and a dash of Coca-Cola), Booker revealed that he doesn’t know the ingredients of a Manhattan or a margarita, either.

The junior senator from New Jersey blushed and chalked up his ignorance to the fact that he doesn’t drink.

“This is brutal,” he laughed. “I might lose some votes from people in my family right now, because they’re, like, embarrassed. They’re embarrassed.”

Booker was right; it really was pretty embarrassing. Even former President George W. Bush, our great Texan teetotaler, knew that a Manhattan contains two parts rye, one part sweet vermouth, and a generous dunking of bitters. You have to know that in most urban areas, and especially in Washington, D.C. This is one of the most drunken cities in the United States — and here mixology is just polite knowledge.

Even if you don’t partake yourself, D.C. booze is almost always flowing freely: at the annual round of Christmas parties, at the open bars during gala season, and whenever some deep-stater testifies in the seemingly neverending impeachment fiasco. It’s inescapable. That the vegan, fitness-obsessed Booker doesn’t seem clued in to any of it shows that he’s either too clueless to comprehend — or worse, willfully ignores — the world in which he resides.

Screw-ups like the Long Island mixup killed Booker’s presidential campaign from the start. It didn’t help that his platform was only a vague gesture at progressivism and that the likes of Sen. Elizabeth Warren (D., Mass.), former Vice President Joe Biden, and South Bend Mayor Pete Buttigieg fit that bill with more verve.

But what really sunk Booker was his inability to read his audience. It’s a historic issue for the man who dubbed himself “Spartacus.” Fundraising and Booker’s enthusiasm have hid it in past cycles. But this time around, a closer look at Booker revealed a strange, awkward man, who spun out the same joke about “dating” coffee for nearly 10 years.

And for most people, that sort of thing is off-putting. Even Booker’s girlfriend, the actress Rosario Dawson, called the coffee jokes “fair game” for mockery. And perhaps the little tics like that explain why she was initially so hesitant to support her boyfriend’s presidential bid.

“Regardless of Cory, I wasn’t going to be behind any particular candidate this election,” Dawson said in September. “I really just want to be behind the electorate.”

How embarrassing. It took the pressure of USA Today and the Washington Examiner for Dawson to admit that she is devoting most of her political attention to “voter registration and the census,” but “of course” she supports her boyfriend’s run.

No need for that anymore. Right now, Booker probably needs a stiff drink. Perhaps his first Long Island?