President Trump with Senate Minority Leader Charles E. Schumer (D-N.Y.) in the Oval Office on Tuesday. (Mark Wilson/Getty Images)

Every time conventional Beltway wisdom congeals as quickly as it did on Tuesday — this time around, the certainty that President Trump had blundered terribly in saying he would in effect “own” any government shutdown over border security funding — analysts ought to think back to the stunned silences around many newsrooms on Election Day in 2016.

Rarely have so many abjectly incorrect experts shrugged off their face-plants of recent vintage to return to high degrees of certainty in so short a period of time. It’s the same class of talking heads that didn’t see 2010 coming, or 2014, or who think they can claim there was a “blue wave” even though Republicans increased their Senate majority by two.

Still, this is the business predictors have chosen, so they have to predict. A contrarian view is anchored by Gov. Doug Ducey’s (R-Ariz.) galloping victory in his reelection bid last month. Ducey talked about border security almost every day during his romp in “purple” Arizona. Not about illegal immigration, but always about border security and about keeping Americans safe from drugs, cartels and human trafficking.

Because more than 70,000 Americans died from overdoses in 2017, millions of people have at least brushed up against fentanyl or other opioids, and have often been terribly scarred by it. Some may know most of these killer drugs come via the mail, but they also know it flows like a vast river northward from the Mexican state of Sinaloa, and with it mayhem and death. Border security isn’t about the “dreamers” or hard-working undocumented people living for decades in the United States. It’s about security. And Trump has declared he is for this security, is willing to engage in budget brinkmanship to obtain it, and is staking the first confrontation in a two-year battle with House Minority Leader Nancy Pelosi (D-Calif.) and Senate Minority Leader Charles E. Schumer (D-N.Y.) on it.

Shutdowns are tricky things politically. Many claim the Democrats won the 2013 shutdown, though the election of 2014 that followed cost Democrats 13 House seats (they had won back eight in 2012 of the 63 they lost in 2010) and nine Senate seats. (The short-lived shutdown in January was an embarrassment for Democrats, and they folded quickly so it is not often mentioned in shutdown scorecards.)

Now, again, Democrats think they framed the Oval Office confrontation on Tuesday pretty neatly. But Republicans are not so sure. Indeed, some are quietly clapping. “Keep those cameras rolling,” they whisper. “Give Nancy and Chuck a 24/7 cable channel.” Most Beltway Republicans aren’t spoiling for a shutdown, but out in Trump Country, the idea of fighting to keep fentanyl out of the country and the cartels at bay — well, Schumer and Pelosi can be against that for the next 23 straight months if they’d like. It’s not a winning issue.

The president has major political challenges, but their extent won’t be known until special counsel Robert S. Mueller III reports, and until the Democrats settle on a 2020 nominee. The idea that the Senate would vote to remove the president from office over a campaign-finance violation is ridiculous — especially in the absence of evidence of collusion that his foes expected to find. But it’s painful for the president to constantly be turned on a political spit on two of three major cable-news channels — channels so addicted to Trump that they barely bothered with Brexit or the Chinese or Iranian perfidies of the day.

What we do know is the Beltway is almost 100 percent convinced that Trump can’t win this showdown on border security. Just like they were convinced he would lose 25 months ago. Just as elites in Britain were convinced that Brexit would not pass, and then that a “Hard Brexit” was impossible. Just as Eurocrats and Time magazine were convinced French President Emmanuel Macron was the man of the moment. Perhaps the D.C. analysts should reconsider their convictions.