The economy grew slowly last quarter, according to a report published Friday, the first official estimate of growth under President Trump. (Evan Vucci/AP)

President Trump came into office promising to make the economy great again — or at least make it grow at rates the United States hasn't enjoyed for decades.

On Friday, he got a taste of just how far he has to go.

The country's gross domestic product, a broad measure of economic growth, grew by a paltry 0.7 percent in the first quarter of 2017, slower than the quarter before it and far from what Trump said he would and could deliver for the American people. During the campaign, he cited figures as high as 6 percent.

Now, that anemic quarter isn't Trump's fault — there's little if anything any president can do in his opening months that would have an instant effect on GDP growth — and it's not even as bad as it sounds.

Despite the disappointing figures in Friday's report, experts believe the economy is doing reasonably well. Official estimates of economic activity in the first quarter often give the impression of a weak economy, in part because of the weather. A winter storm can halt a construction project, or keep shoppers off the street. By contrast, unusually warm weather can discourage consumers from spending on wintry items.

The U.S. economy posted its weakest first quarter growth in three years as consumers crimped on spending. (Reuters)

The bad news for Trump is that while the economy may be sound, it's not roaring, and a host of longer-term factors — which Trump didn't cause but also can't fix — mean it's unlikely to hit rocket growth any time soon.

One factor is the age of the labor force. Although more Americans have gone back to work since the financial crisis eight years ago, the number of workers who are available has been declining as baby boomers retire. That trend limits how much the economy can produce.

Trump's allies say he can restore the economy to its level under President Ronald Reagan. After an initial recession during his administration, GDP skyrocketed 7.3 percent in 1984, and continued to expand rapidly for the rest of his term.

Yet Reagan had advantages that Trump will not. When Reagan was in office, the labor force was expanding rapidly as women went to work in the formal sector. Meanwhile, the economy was on the verge of a technological boom.

“The evidence shows clearly that no feasible tax reform in this country will raise economic growth to 3 percent on a sustained basis,” said Douglas Elmendorf, a former director of the Congressional Budget Office, in a recent interview with The Washington Post.

Trump's task is complicated by the Federal Reserve, which after nearly a decade of attempting to stimulate the economy, is now trying to make sure it doesn't run too hot. At their meeting last month, Fed officials said the economy was performing according to expectations and that they planned additional hikes in interest rates if the current trend continued. Investors are expecting another increase in June.

And while every president hopes for a roaring economy, under the tax outline Trump put out this week, he's officially betting the country's finances on it.

The White House is counting on economic growth to be able to cut taxes without adding to the national debt.

Trump aims to reduce taxes sharply, especially on businesses, but his advisers say that there is no need to bring down government spending at the same time. Instead, they argue, the cuts will stimulate rapid economic growth, allowing the government to go on collecting the same amount of money in taxes despite reduced rates.

If that growth does not materialize, then the government will have to borrow more to make up for the forgone revenue. And sooner or later, that bill comes due.

In short, if Trump succeeds is passing his tax plan but can't deliver the economy he promised, it won't just be his problem. It will be a problem for his successors, and for the next generation of taxpayers too.