A letdown, to be honest. I had all my chips on a secret foreign plot to kidnap the vice president.

Extremely unlikely, I know. But remember that American politics is essentially a gonzo television show now. “The vice president gets kidnapped” seems not only plausible but sort of inevitable as a subplot. Although maybe for one of the later seasons, after the writers have run out of marginally more realistic storylines.

Anyway, the solution to the mystery of why Pence had to be pulled off the tarmac before embarking for New Hampshire for an event turns out to be simple: He was walking into a terrible photo op and didn’t know it.

If Pence stepped off the vice presidential aircraft, one of the people he would have seen on the ground was under investigation by the Drug Enforcement Administration for moving more than $100,000 of fentanyl from Massachusetts to New Hampshire.

Jeff Hatch, who agreed in federal court Friday to plead guilty and will face up to four years in prison, works for an opioid addiction treatment center in southern New Hampshire that Pence was set to visit. A former New York Giants player, he has spoken publicly for years about his own challenge with drug and alcohol addiction, which ended his football career…

Federal court documents released Friday said Hatch was caught in 2017 with 1,500 grams of fentanyl. A baggie of the drug sold on the streets of New Hampshire is usually about one-tenth of a gram.

Apparently Hatch tried to sell some of the fentanyl to an undercover agent, was nabbed, and then agreed to cooperate with the feds to help them pinch people in his supply chain. He ended up with a slap on the wrist, a four-year prison term according to the plea agreement that was revealed Friday. That’s what Trump meant when he said after Pence’s mysterious cancellation that we’d know in two weeks why he had to skip the opioid event. Evidently that was when the feds planned to reveal Hatch’s plea deal. Until then, the White House couldn’t spill the beans or they’d risk blowing his cover as an informant. They must have only learned of Hatch’s criminal jeopardy at the last second before Pence’s departure.

Imagine Mike Pence posing for a grip-and-grin with Hatch upon arrival in New Hampshire, only to have that photo plastered everywhere in lefty media two weeks later when Hatch’s drug-dealing activities were revealed. It would have been a dirty hit — again, Hatch was cooperating with the DOJ to take down other dealers and Pence could have justified going through with it on grounds that canceling at the last minute might have tipped off the bad guys that the feds knew what Hatch was up to. But lefties would have eagerly circulated the photo anyway. In the end, the White House spared itself a headache.

Eh. Lame ending! Time to move onto the other gripping minor mystery story circulating on the news wires right now. The case of the long-distance hamburger:

The popular West Coast burger chain In-N-Out said Monday it could not solve the mystery of a New York man who discovered one of its burgers sitting untouched on Queens street…

Santa Monica native Lincoln Boehm, 31, told The Post Sunday that he found the pristine, wrapped In-N-Out double-double and that the discovery “genuinely shook me to my core.”

Boehm wondered how the burger had gotten there and how it had remained looking “as if it had come off the grill five minutes ago.”

There are no In-n-Outs east of Texas. How’d a fresh burger land on a street on Queens? I mean, apart from the obvious mundane explanation that Boehm’s lying about having taken his photo of a burger lying on asphalt in New York. Or that someone brought some In-n-Out with them on a flight home to NYC from out west and then got careless at the curb outside their apartment when they were focused on unloading their luggage from the cab. Stay tuned.