To pass a law in the United States, you need to jump through a lot of hurdles.

A bill has to first clear a committee in the House or Senate. (In the case of Republicans’ tax legislation this year, its components had to clear 11 different committees.) The House Rules Committee has to agree for it to come to the floor for a vote. It has to pass that vote. In the Senate, it has to get 60 votes to beat a potential filibuster, or else obey a set of byzantine rules allowing it to pass with a simple majority.

But another entity gets a vote, an entity not mentioned in the Constitution or in congressional rules or even physically located in Washington, DC. That entity is the bond market, and right now, it is very pissed.

Currently, the US makes up for any budget deficits it incurs by issuing bonds of various durations to cover the difference. It auctions those bonds — essentially IOUs issued by the Treasury Department — on the open market, where investors (banks, hedge funds, foreign central banks, pension funds, etc.) can bid on them.

To get them to bid, the US has to pay interest on the bond. And when the US borrows a lot, and especially if its fiscal policy indicates that the country may reach a point where it can’t pay back what it owes, investors will demand to receive more interest to compensate for the risk of default. That means the US has to pay more every year to service its past debt, and those payments in turn become future debt. If the interest they demand is high enough, the result can be an economic downturn, an upward debt spiral, or both.

While politicians pay attention to all kinds of economic indicators, from the unemployment rate to the stock market, the bond market is a different and more powerful animal. The most famous quote about the bond market’s power comes from former Bill Clinton adviser James Carville: “I used to think if there was reincarnation, I wanted to come back as the president or the pope or a .400 baseball hitter. But now I want to come back as the bond market. You can intimidate everybody.”

History is littered with cases of governments that were forced to abandon policies — or that even fell from power — because the bond market revolted. Just a few years ago in the UK, a mass sell-off by currency and bond traders forced the Tory government to abandon its plans for a massive deficit-ballooning tax cut and axe Chancellor of the Exchequer Kwasi Kwarteng, before then-Prime Minister Liz Truss herself was forced to resign after just 45 days in office. Banks like Citigroup were openly declaring that unless the UK got a different prime minister, the markets would continue to punish it. That is power.

Now, Congress is weighing a reconciliation bill that would increase the deficit by at least $3 trillion over 10 years, and possibly closer to $5 trillion if some of its temporary components become permanent, as seems likely. This is a big increase in America’s already substantial debt burden and

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