Investment has also followed a surge in profits, reflecting stronger GDP growth, as it tends to.
As workers become scarcer in America's tightening labour market, firms have a greater incentive to automate.
A second boon of a maturing cycle is higher productivity, which has risen at a snail's pace in all countries since the global financial crisis.
More capital spending by businesses will help.
And in America, in particular, firms are under pressure to reorganise their businesses to meet expanding demand, because low unemployment makes it harder to find additional workers.
America is not about to return to pre-2005 rates of productivity growth, whatever Mr Trump tweets.
But there are tentative signs that the rate is starting to pick up from its dismal, post-crisis slump.
All expansions eventually come to an end.
Even if America does not inflict a recession on itself—through ill-judged trade policies, say—a global shock could do the job.
When that time comes, America's policymakers will end up regretting how government revenues were squandered on a badly designed tax cut.
The deficits that result will make it politically harder for Congress to agree on a fiscal stimulus to combat the next downturn.
Interest rates will in all likelihood peak at much lower levels than in the past, limiting the scope for big cuts to fight a recession.
In this, the worrywarts are entirely correct.
But the immediate outlook is sunny.
The global upswing is still young, and has momentum.
Mr Trump's policies have lifted the spirits of business leaders, who already had reason to be confident.
Galling though it must be to the president's critics, America's economy is well placed for 2018.