There is a terrifying concept in financial history known as Ferguson’s Law.
Coined by the brilliant financial historian Niall Ferguson, the law is brutally simple. It states that an empire reaches a critical, irreversible inflection point of decline the exact moment it spends more money servicing the interest on its national debt than it spends on its own national defense. It is the ultimate tipping point. It is the moment the bill truly comes due.
Depending on how you measure the math, the United States of America is currently in violation of Ferguson’s Law.
This staggering reality is exactly how we kick off the newest episode of the Earn & Invest podcast. I sat down with Robin Wigglesworth, the editor of FT Alphaville and the author of the incredible new book A Fabulous Debt: The Epic Story of How Bonds Built the Modern World.
I know what you are thinking. Bonds. They are boring, right? They are the sleepy, passive safe assets we stuff into the 20% of our 80/20 portfolios just to make sure we don’t lose our shirts when the stock market throws a tantrum.
Robin completely shattered that illusion for me.
He describes the bond market not as a sleepy safe haven, but as the absolute “dark matter of finance.” It is the invisible, massive foundation that secretly ties the entire global financial system together. It is significantly larger—and vastly more powerful—than the stock market and the banking system combined.
The history of this dark matter is absolutely wild.
It all started in 12th-century Venice. The original bond, known as the Prestiti, wasn’t an investment tool at all—it was a forced tax to fund a war. But when Venice lost the war and couldn’t pay its citizens back, they made the interest-bearing receipts tradable at the Rialto market. That pure, accidental innovation birthed the world’s first liquid bond market.
From there, debt literally built the modern world. The Dutch built a wildly successful bond market because of a strict cultural ethic to always pay their debts—so much so that some of those ancient 400-year-old Dutch bonds are still paying interest today. Great Britain leveraged its massive console bond market to out-fund its rivals during the Napoleonic Wars. When the wars ended, the ensuing bond rally provided the massive influx of wealth that single-handedly capitalized the Industrial Revolution. Even Alexander Hamilton took frantic notes, realizing the U.S. desperately needed to copy British finance if it wanted to survive.
But with massive power comes massive, systemic risk.
We completely forget that the 2008 financial crisis was not a stock market crash. It was fundamentally a bond market crash. Financial engineers in the 70s and 80s figured out how to package individual mortgages, student loans, and credit card debt into tradable bonds through securitization. When the underlying due diligence on those securitized mortgages completely failed, the entire global banking system keeled over.
And when traditional interest rate cuts failed to stop the bleeding in 2008—and again during the 2020 pandemic—central banks turned to Quantitative Easing. QE is nothing more than massive, unprecedented bond buying by the Federal Reserve to inject liquidity into a dying system. It created wild financial excesses, yes, but Robin argues it successfully prevented a total global economic collapse.
Human nature never changes. We continuously invent complex, highly leveraged debt products. We take excessive, ridiculous risks until the entire system shatters. We learn our lesson, exercise temporary caution, and then repeat the exact same cycle a generation later.
Bonds aren’t boring. They are the terrifying, magnificent engine of the world.
You absolutely have to listen to this conversation with Robin. It will completely change how you view your portfolio, global politics, and the money sitting in your bank account right now.
A Quick Note for My Chicago People
Before you go, I want to invite you to hang out with me in person! On Saturday, October 3rd at 7:00 p.m., we are hosting an informal Earn & Invest meetup and mastermind gathering at The Duke of Perth right here in Chicago. Come grab some incredible fish and chips, have a pint, and let’s build some real community. I would love to see you there.
Really interesting way of framing it. One thing I’ve learned from looking more closely at bonds from a portfolio-construction angle is that “bonds are defensive” is far too broad a statement. Sometimes they genuinely diversify equities; other times they mainly help because they fall less.
That doesn’t make bonds unimportant - quite the opposite, as you’ve shown here. It just makes me think the more interesting question for investors is not whether bonds matter, but when they actually deserve a place in the portfolio.