John Mauldin is an investment advisor who often explores the big picture on economic matters in his thought-provoking weekly columns. In his March 30, 2016 column, he weighs a what if scenario: What will the next recession mean for the state of the U.S. federal government’s finances?

He starts by describing the U.S. government’s current fiscal reality:

Next year, the US national debt will top $20 trillion. The deficit is running close to $500 billion, and the Congressional Budget Office projects that figure to rise.

Add another $3 trillion or so in state and local debt. As you may imagine, the interest on that debt is beginning to add up, even at the extraordinarily low rates we have today.

Sometime in 2019, entitlement spending, defense, and interest will consume all the tax revenues collected by the US government. That means all spending for everything else will have to be borrowed.

The CBO projects the deficit will rise to over $1 trillion by 2023. By that point, entitlement spending and net interest will be consuming almost all tax revenues, and we will be borrowing to pay for our defense.

Let’s look at the following chart, which comes from CBO data:

By 2019, the deficit is projected to be $738 billion. There are only three ways to reduce that deficit: cut spending, raise taxes, or authorize the Federal Reserve to monetize the debt.

Make no mistake, these three things are already happening today. The incomes that some Americans born after 1954 can collect in Social Security benefits are being cut effective at the end of this month. The tax rate that Americans who don’t buy health insurance either on their own or earn through their employer is doubling to 2% of their annual taxable income on their IRS tax returns this year, and it will increase further when it comes time to file taxes next year. And who could have missed the Federal Reserve working overtime from 2009 through 2014 to become the largest single creditor to the U.S. government as a result of its funding of the national debt to support the U.S. government’s spending through its quantitative easing programs.

Mauldin notes one of the more incredible assumptions built into the Congressional Budget Office’s economic forecast for the next 10 years. The CBO assumes that there will be no recession in the U.S. economy at any time during those next 10 years.

He then worked with one of his colleagues to estimate how much the U.S. government’s current fiscal reality chart would change if another recession, the size of the 2008-09 recession, were to take hold in 2018. Here’s what he found:

Here’s a chart of what a recession in 2018 would do.

Entitlement spending and interest would greatly exceed revenue.

The deficit would balloon to $1.3 trillion. And if the recovery occurs along the lines of our last (ongoing) recovery, we will not see deficits below $1 trillion over the following 10 years—unless we reduce spending or raise revenues.

The last seven years have been one big lost opportunity to reign in spending to levels that would avoid the next recession from sparking another massive fiscal crisis.