Remember the old saw about the salesman who loses money on every sale but thinks he can make up the shortfall by selling in volume?

That's what comes to mind every time I hear people say that President Donald Trump is being shrewd by pandering to his base.

Consider last week's remarkable Oval Office meeting between Rep. Nancy Pelosi (D-Calif.), Sen. Chuck Schumer (D-N.Y.) and Trump. (There is photo evidence, but no audio, to suggest that Vice President Mike Pence was also in the room.) What was supposed to be a brief photo-op turned into a dramatic confrontation when the president invited television cameras to stay for the conversation.

As always happens after one of these political reality-show spectacles, the chattering classes set out to score the bout. According to conventional rules, Pelosi and Schumer came out the winners. They got Trump to admit that if there's a government shutdown over border wall funding, it will be all his doing. (Just before the meeting, congressional Republicans were pre-spinning a "Schumer shutdown.") Pelosi solidified her claim to the House leadership while Trump made future bipartisan deals with the Democrats — something he reportedly wants — less likely.

According to The Los Angeles Times' Eli Stokols, even Trump realized he was taken when it was over: He "stormed out" of the meeting and threw a folder of briefing papers across the room.

Yet there was a loud contrarian analysis that said Trump came out a winner. Why? Because his base loves this stuff.

"If you are a supporter of the president's policies," wrote the Daily Beast's Matt Lewis (no Trump booster himself), "this was an especially welcome display — a rare example of a president publicly fighting for his policy goal: a border wall."

Across Fox News opinion shows and right-wing talk radio, the view that Trump won was nearly unanimous.

Even Yahoo News' Matt Bai, a decidedly left-leaning observer, excoriated liberals for not understanding that "Trump knows that every time he flouts the staid convention of the office, every time he does the thing that seems inappropriate among the political set, he's winning with the chunk of the electorate he still has."

Sure. The problem is that chunk is not a majority.

Bai's larger observation, that Trump is so embattled he can't afford to lose his hard-core supporters, is a good one in the context of gaming out how Trump can survive impeachment. When looking at what advances this administration's agenda or is good for the Republican Party, however, "his base loves it" doesn't score any points.

Worse, it's self-fulfilling prophecy. As he sheds the mostly suburban voters who gave him his margin of victory in 2016, of course he clings more tightly to those who celebrate the behaviors that are bleeding the GOP of support. They're the only ones left. Proclaiming that "his base loves it" may be an explanation, but it's no excuse. And it misses the point if you care about the GOP's long-term viability or even Trump's re-election prospects. He's going to need more voters than his amen chorus.

Last month's midterms showed what a national election looks like when only Trump enablers feel highly motivated to vote Republican. The GOP lost Orange County, Calif., the ancestral home of the conservative movement. New England now has more GOP governors than Republican members of Congress. In Iowa, the GOP lost all of its House races save for uber-Trumpy Steve King's. A party in which only bigoted goons like King can thrive by fueling white resentment is destined for the dustbin of history.

The irony here is that Trump's base will forgive him for nearly anything. He easily could have used the wall as leverage to gain Democratic support for mandating that all employers use E-Verify to confirm a prospective employee has legal immigration status. This is what serious immigration hawks have implored him to do — and he'd get credit for being the great deal-maker he claims to be.

But the larger irony is that servicing his base has led him to this very predicament: shutdown or back down.

Most presidents try to expand their coalitions while holding onto the base. Trump has shrunk his coalition and laid the foundation for future shrinkage by forcing his party to endorse this behavior. Trump will be gone soon enough, but at this rate the party of Trump will be a rump party.

Jonah Goldberg is an editor-at-large of National Review Online and a visiting fellow at the American Enterprise Institute.

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