Howard Schultz is right about the debt. Too bad no one will listen to him.

Now, there are plenty of good reasons to summarily dismiss a possible presidential run by the former Starbucks boss. Let's start with the biggie: This political novice has no natural home in either major party. Democrats have moved even further left since 2016, when the moderate Schultz was supposedly mulling a challenge to Hillary Clinton. But Schultz doesn't seem to have drifted leftward at all. He eyerolls the idea of single-payer health care, for instance, and stiff arms journalists when they try to describe him as a liberal, preferring "centrist."

What's more, Schultz is a pretty low-key dude — President Trump might even call him "low energy" if they ever faced off in a debate — when Democrats are going to want a candidate ready to hit Trump hard. (Maybe literally.) They're looking for a triple shot of espresso from their candidate, not a cup of green tea.

The politics of an independent run don't look much better, even if Schultz spends a good chunk of his coffee-hawking fortune. Maybe one in 10 voters really play it down the middle, leaning neither Democrat nor Republican. And while the billionaire businessman might offer an escape route for conservative NeverTrumpers disgusted with the GOP's current billionaire businessman leader, there really aren't that many of them. Nearly 90 percent of Republicans approve of the job Donald Trump is doing as president.

For an independent candidacy to catch fire, there needs to be a galvanizing issue — something that goes to the heart of American peace and prosperity. And this really gets to Schultz's core problem. Maybe America's, too. He thinks there's a big crisis happening out there. But the rest of the country doesn't.

As he told CNBC on Monday, "I think the greatest threat domestically to the country is the $21 trillion debt overhanging America and future generations. … We have to go after entitlements."

Schultz is right to worry about America's catastrophically ballooning debt. But no one will listen to him.

Certainly no one is going to win the Democratic nomination in 2020 making this argument. The days are over when some Democrats would whisper about a grand bargain with Republicans in which they would agree to cut future Medicare and Social Security spending in exchange for higher taxes on the rich. Instead, look for many of the 2020 Democratic presidential contenders to push for expanding Medicare and Social Security, not restraining it.

Why don't many of Schultz's fellow Democrats share his debt alarmism? Maybe they've noticed that financial markets don't seem too worried with a doubling of the federal debt-to-GDP ratio over the past decade and projections for it to double again over the next few decades? But Democrats are also reacting to how Republicans professed deep concern about the rising national debt and trillion dollar budget deficits under President Obama, but little concern about rising debt and deficits under Trump. If Republicans can ignore supposed debt concerns to get something they want, such as tax cuts, then Democrats should do the same to obtain their favorite policy priorities. And don't forget: Trump ran for president promising to leave Social Security and Medicare alone.

But make no mistake: Schultz is far more right than wrong. A new government report finds that for the first time since 1982, Social Security will spend more than it raises in revenue and collects in interest. Federal spending on entitlements overall has more than doubled as a share of GDP since 1970, and is on pace to gobble up all federal revenue by mid-century. Trillion-dollar budgets will soon be a permanent state of federal finances, according to both Wall Street and government bookkeepers. If interest rates move back to historically normal levels, we will be paying more on debt interest than national security.

This is fiscally nuts. There is no need to risk the long-term health of the American economy by making an unnecessary wager that mainstream economics is wrong and massive government borrowing won't eventually crimp private investment and economic growth.

It's a good thing Schultz is talking about debt. But an economy of steady growth and low unemployment makes a crisis message a tough sell. And a presidential run to raise its profile would be even better. It's just too bad that no one who cares as much about it as he does is likely to occupy the Oval Office anytime soon.