Basic math and what the Wall Street Journal calls “Trumponomics” are headed for a brutal collision.

Here’s why.

The national debt is $20.6 trillion and rising. With rates low, annual debt interest costs averaged about $250 billion from 2011 through 2016. As the economy improved, interest rates slowly ticked up. But, now they are expected to surge as the stimulus jolt to an economy already at full employment from Trump’s $1.5 trillion tax cut package plus over $300 billion in added government spending drive up inflation – and interest rates – over the next 10 years.

Oh, those tax cuts and spending will also push annual deficits above $1 trillion for the foreseeable future, jacking up the debt even more as interest rates surge.

Basic math says higher interest rates times huge and growing debt equals much higher interest costs.

How high?

The Peter G. Peterson Foundation, created to raise awareness of America’s long-term debt and how it affects economic growth, projects “interest costs will triple over the next 10 years, soaring from $269 billion in 2017 to $818 billion in 2027.”

Even worse, the Foundation says interest costs “are projected to be the third largest category in the federal budget by 2026 (after just Social Security and Medicare), the second largest category in 2046, and the single largest category before 2050.”

Larger than Social Security and Medicare? Wow!

Surely, “conservative” Republican leadership can do this basic math?

Maybe not.

“When Democrats are in power, Republicans appear to be the conservative party, and when Republicans are in power, there is no conservative party,” Sen. Rand Paul told TIME Magazine. While on the Senate floor he said, “I can’t in all good honesty, in all good faith, just look the other way because my party is now complicit in the deficits.”

Former conservative Republican Rep. Jason Chaffetz chimed in, telling Fox Business, “Republicans have lost every single bit of credibility on the idea that they care at all about debts and deficits.”

Sounds like reducing deficits and debt is not a real Republican issue, just one that plays well with the base.

Case in point: In 2013 Sen. Mitch McConnell said, “the most important issue confronting the future of our country is our deficit and debt.” That’s the same Mitch McConnell who just ignored the deficits and debt to pass the tax cuts and budget bill.

Tom Nichols, a professor of national security affairs at the Naval War College and self-proclaimed long-time Republican, expressed the growing consternation among many long-time Republicans in a USA Today op-ed.

“Republicans once believed in limited government, fiscal restraint, support for the defense and national security establishments, family values, and a strong American role in maintaining global order,” he wrote. “More than that, we were the party that believed in logic and prudence over emotion. Our hearts were perhaps too cold, but never bleeding. Today’s Republicans, however, are a party of bellowing drama queens whose elected representatives blow up spending caps, bust the deficit, and attack America’s law enforcement and national security agencies as dangerous conspirators.”

So, maybe the problem is much larger than not knowing basic math. It’s not having and adhering to real tenets of conservative Republicanism.

Crawford (crawfolk@gmail.com) is a syndicated columnist from Meridian.