The U.S. economy, by some measures, has recovered from the Great Recession: The unemployment rate is only half what it was at the worst, real gross domestic product is about 10% larger than the previous peak, and personal wealth has risen by more than $20 trillion as the stock market and the housing market have bounced back.

But everyone knows the recovery has been uneven.

Total employment may have grown by 6 million since the recession began in 2008, but employment in manufacturing is down nearly 1.5 million. Real disposable incomes may be up by 16%, but because most of the increase has been captured by the richest sliver of society, the median family’s annual inflation-adjusted income is still down more than $3,000.

Most troubling, there’s still very little investment in the buildings, equipment and intellectual property that we ought to be putting into place today as the foundation of our prosperity tomorrow.

Who’s preparing the United States for the 21st century? Nobody, really. Not the 22 million private businesses, not the 118 million households, and not the 90,000 state, local or federal government agencies.

Since the recession, investments have fallen sharply, and they haven’t gotten back up again. It seems that everyone is still scarred by the Great Recession, and by the collapse of asset bubbles in 2000 and 2006.

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Gross domestic investment totaled about $3.6 trillion in the second quarter of 2016, about 20% of gross domestic product. That may seem a large sum, but it’s the lowest share of GDP, except during recessions, since 1947.

And, unfortunately, even that weak number grossly exaggerates the actual contribution of this investment in creating new productive capacity for the economy. Why is the figure exaggerated? Because these data are reported on a gross basis, without subtracting the depreciation of capital assets such as equipment, buildings, software and the like.

After you subtract the capital that’s used up, net investment totaled only about $750 billion in the second quarter, or 4% of GDP, about half of the average over the post-war period. In fact, net investment has been running at the lowest rates since the Great Depression of the 1930s, suggesting that U.S. investment itself is in a depression.

Businesses won’t invest

Everyone knows by now that business investment has been extremely weak, especially during the recovery from the Great Recession.

Business fixed investment has fallen for three quarters in a row, the first time that’s happened outside of a recession or its immediate aftermath since the mid-1980s. Investments in oil-drilling equipment and structures tanked in 2015 when the price of oil fell, and haven’t recovered. Investments in information-processing equipment (such as computers and semiconductors) have risen at the slowest pace in the post-World War II era.

Business investment remains very subdued.

Net investment by private businesses briefly rose to a little more than 3% of GDP in 2014 before the collapse in oil prices. It fell to only 1.9% of GDP in the second quarter, about half of the post-war average.

On Thursday, the Census Bureau reported that core capital-equipment orders jumped 1.6% in July after a 0.4% gain in June, reversing months of declines that left capital spending down 7.1% in the past 12 months. Some economists said the report on durable-goods orders indicated that business investment would increase in the second half of the year, but no one is predicting a return to pre-Great Recession levels any time soon.

Why aren’t businesses investing more? Because there is already too much productive capacity in the world for the level of demand. Prices are generally falling or growing only tepidly, especially for manufactured goods. Vacancy rates for stores and offices are high. There is no great need to invest in high-tech equipment such as computers or chips because there haven’t been any great leaps forward recently. The old equipment works fine. (I’m using a six-year-old computer to write this.)

One bright spot: Gross investments by businesses in intellectual property have accelerated in the past few years, and are now at a record 4.1% of GDP. (Unfortunately, there is no available data on net investment in intellectual property.)

Equally bleak

The business investment story is well-known, but fewer people are aware that investment by households and government agencies is equally bleak, but for different reasons.

What do households invest in? Mostly real estate. After the housing bubble burst about a decade ago, home buyers became more cautious. Few buyers believe today that real estate is a sure-fire way to double or triple their money.

Slower population growth is also working to reduce the need for additional housing units.

As a result, net investment by the household sector was just 1.3% of GDP in the second quarter, about half of the post-war average. New construction will probably increase modestly in coming years, but no one expects the same level we saw in the bubble years, or in the 1950s and 1970s when millions of housing units were built each year.

Government investment has collapsed since the Great Recession.

Net investment by government has also collapsed since the Great Recession. The reason is simple: fear (mostly irrational). As many people have pointed out (including Hillary Clinton and Donald Trump), the government ought to be investing more right now in basic infrastructure, because the benefits are high and the cost is low. (The government can borrow money at 2.25%.)

The economic stimulus proposed by President Barack Obama and passed by Congress in 2009 increased federal investments modestly (on such things as highways, high-speed internet, high-speed rail, environmental cleanups and green energy), but investments by state and local governments declined by an equal amount.

And once the stimulus was spent, the Republican Congress clamped down on investment spending in a fit of moral outrage. Net investment by the federal government has actually been negative for 10 straight quarters, which means more capital is consumed each quarter than is created.

The story is nearly the same at the state and local government level, which builds most of the roads, schools and transportation infrastructure.

Borrowing costs for state and local governments are low (around 2.85%), but lawmakers and taxpayers have balked at spending more on infrastructure because of the public’s strong sentiment not to spend, borrow or tax. New issuance of municipal and state bonds has fallen to the lowest level in 20 years, the Wall Street Journal reported.

As a result, net investment by state and local governments dropped to 0.6% of GDP in the second quarter, about half the average over the post-war period.

We have an economy that’s underperforming, but no one is willing or able to invest the sums needed to build the offices, factories, mines, computers, machinery, roads and airports we’ll need in the future. Business leaders don’t see a quick payoff in long-term investments, and public officials can’t fill the gap because the public thinks austerity now is better than growth tomorrow.

Somewhere, someone needs to find some courage, or we’ll be doomed to decades of disappointing growth.