John Mauldin sends a cheery reminder that you can't borrow your way to prosperity--or, more bluntly, that you can't solve a debt problem with more debt.

The U.S.'s current budget assumptions predict that we will need to borrow at least $1 trillion a year for the next 5-10 years. $1 trillion is actually a lot of money.

The $1 trillion has to come from somewhere. U.S. consumers are now saving a bit, which will help, but they aren't saving THAT much. Our usual lenders (e.g., China) have shown signs of pulling back. The Fed can't "monetize" the debt forever, or its balance sheet will consume the entire economy.

("Monetization" is when the Fed buys Treasuries in exchange for "cash," printing more money in the process. Theoretically, the Fed could create every dollar the country needed to borrow. If it did this, however, the money supply would expand by the amount the country borrowed every year. There would be that many more new dollars chasing the same amount of old stuff, and the value of the dollar would plunge. We would soon be paying $100 for a carton of milk).

The underlying message of John Mauldin's note is this:

What can't go on forever...won't.

Two possible outcomes, therefore, are:

Soaring interest rates, as the bond market finally refuses to lend the country more money and foresees hyper-inflation, OR

Crushing deflation, a lost decade, and a massive buildup of debt like Japan (Japan is proof that you can run vast deficits forever and not end up like Zimbabwe in the near future.)

There is also, thankfully, a third possibility, which is that the economy will settle back into a solid growth rate, the government will gradually get its spending under control, tax receipts will come in higher than expected (reducing the deficit), and the Fed will perfectly manage to reverse its money-printing before inflation gets out of control. Here's keeping our fingers crossed...

John Mauldin:

$1.5 trillion dollars means that someone has to invest that much in Treasury bonds. Let's look at where the $1.5 trillion might come from. Let's assume that all of our trade deficit comes back to the US and is invested in US government bonds. Today we found out that the latest monthly trade deficit was just over $30 billion, or $370 billion annualized (which is half what it was a few years ago). That still leaves $1.13 trillion that needs to be found to be invested in US government debt (forget about business and consumer loans and mortgages).

Killing the Goose

$1.13 trillion is roughly 8% of total US GDP. That is a staggering amount. And again, that assumes that foreigners continue to put 100% of their fresh reserves into dollar-denominated assets. That is not a safe assumption, given the recent news stories about how governments are thinking about whether to create an alternative to the dollar as a reserve currency. (And if I was watching the US run $1.5 trillion deficits with no realistic plans to cut back, I would be having private talks too. They would be idiots not to do so.)

There are only three sources for the needed funds: either an increase in taxes or people increasing savings and putting them into government bonds or the Fed monetizing the debt, or some combination of all three.

Now the Fed is in fact monetizing a portion of the debt as part of its quantitative easing program, and US consumers are saving more. Tax receipts are way down. I can tell you there is a great deal of angst in New Orleans tonight about the Fed monetization. This is traditionally a "gold bug" conference, and many of the participants and speakers see only inflation in our future.

Long-time readers know that I think the Fed has been able to get away with its rather large monetization program because of the massive deflationary forces let loose in the world by the credit crisis, which is forcing a monster deleveraging regime all over the world. Where has all the money gone that the Fed has printed? Right back onto the Fed's balance sheet as bank reserves. The banks are not lending, so this money does not get into the system in the usual manner associated with fractional reserve banking. Until that happens, and is accompanied by increasing wages and employment, inflation is not in our immediate future.

And this brings us to our conundrum. You cannot continue to run deficits significantly larger than nominal GDP for too long without risking the demise of the economic system. Ask Argentina or any of the other nations where hyperinflation occurred, as detailed in the study mentioned above. But we are in a deflationary environment, so the Fed can monetize the debt far more than any of us suppose without risking immediate and spiraling inflation.

But there is a limit to the Fed's ability to do so without causing real inflation. First, as long as the Fed is independent, at some point they will simply have to tell Congress we can no longer monetize the debt. While I am sure that some of you doubt they would do so, the Fed officials and economists I have been around are pretty adamant about that. There is a line they will not be pushed past. It may be further than I like, but it is there.

The Fed cannot simply buy up all the debt needed to fund the government. Again, no one on the FOMC would either advocate or allow that. That would in fact start us down a very dangerous path rather quickly. Therefore, they must have a large number of willing bond buyers outside the Fed. The good news, gentle reader, is that we will find someone to buy that debt. That is also the bad news. Let's go back 30 years.

Legend now has it that Paul Volker single-handedly took the inflation bull by the horns and ripped them off. Now, it took fortitude to do that in the face of certain recession and high unemployment. Those were not fun days. But his partner in the deed was the bond market. Bond investors simply demanded higher returns, because they were really worried about inflation.

At some point, if we do not get the government deficit under control, the bond market is once again going to react. Seemingly overnight, real (inflation-adjusted) rates are going to rise, and will do so rapidly. And I am not talking about 1 or 2%. You just cannot have 8% of a $14-trillion GDP go into US government debt every year, forever, at today's low real rates.

Let's play a thought game. If you take 8% of US consumer spending and save it, and it finds its way into government bonds, you have reduced consumer spending and therefore the actual GDP. But how about those who want to invest in stocks? Foreign bonds and currencies? New businesses? Loans of all types? How much are we going to have to save to get the necessary capital? How high will the saving rate have to be to finance all those other activities in a world where debt securitization is still anemic?

Some will point to Japan and their government debt-to-GDP ratio, which will soon be over 200%, a far cry from where we are today. Why can't we grow our debt to 200%? Because the Japanese have long had a culture of saving and investing in government bonds. It's what you do to support the country. But even they will run into a wall as their savings rate continues to drop, because so many of their citizens are retired and are now selling bonds to finance retirement. They too are running massive fiscal deficits, on the order of the size of the US deficits. And does anyone really want to have two lost decades, like Japan?

How long can we go before there is an upheaval? I don't know. The markets can remain irrational or complacent for a lot longer than most of us think. It could be years. Or not. Suddenly, it will be July 2008 and the bond vigilantes stampede.

But now, we seemingly can borrow with no consequences. The deflation that is in the air, plus the lack of bank lending holds, down the normal inflation impulses. We as a nation are leveraging ourselves up. We're partying like it's still 2005. The music is playing and we are dancing. Our Congress is trying to figure out how to run even higher deficits.

At some point, the consequences will be significant. There are two paths, and it is not clear which one we will take. First, we might see inflation kick in and actual rates rise. Since so much of our national debt is short-term debt, that means yet another rise in the deficit as rates rise. Mortgage rates rise, putting pressure on the housing market. There will be even more pressure on commercial mortgages. Consumer debt will be harder to get and cost more. It will mean funding costs for businesses will rise, and that hurts employment. It would be a return to the 1970s of high interest rates and stagnant growth in a very slow-growth environment.

Second, we could see deflation kick in and, even though rates stay more or less where they are, real (after-deflation) rates could rise as they did in the '30s and in Japan.

Some of my most knowledgeable friends argue for the inflation side, and others take the deflation side. I tend to think the Fed will fight deflation until we get inflation, but the consequences will not be pleasant. There is no benign path.

How can we avoid such an upheaval? The only way is to make some very difficult choices. There have to be some adults making the choices, as the teenagers now in control clearly cannot make them.

As I have written in the past, we can run deficits of 2% of GDP for a very long time, which in a few years would be about $300 billion. It is my belief that if the bond market and world investors saw a credible plan to put us on a path to a deficit no larger than 2% of GDP, the dire upheaval that is in our future could be avoided.

But that will mean some painful choices. It is not a matter of pain or no pain, it is just deciding when and how bad it will be. The longer we wait, the worse the consequences.

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