Trump agenda a wild card for Street rally

Get ready for the second-half slowdown.

The US stock market is off to its second-strongest start to the year since 2000, fueled largely on hope for Trumponomics. But Wall Street is bracing for a pullback in the second half, as worries mount over the president’s chances to slash taxes and fix the nation’s health care and infrastructure.

“It’s been an explosive rally in the first half,” Peter Cardillo, chief market economist of First Standard Financial, told The Post. But “the market could be headed for short-term turbulence if there’s no tax reform.”

The S&P 500 index this year has soared 8.3 percent as of Friday’s close, its second-best run since 2013 when it jumped 15 percent. By comparison, the S&P had climbed a meager 1.9 percent by this time last year.

But Wall Street forecasters see less exuberance ahead as President Trump will be under pressure — and a tighter timeline — to deliver.

The market “had the basis and fundamentals for the rise,” Cardillo said. “But we may have gone over on the hope.” Other strategists are cautious, too. “The upside is going to be challenging in the second half — though not necessarily negative,” Bruce Bittles, chief investment strategist at Baird, told The Post.

In addition to the Trump-fueled optimism in the market, Bittles also pointed to unexpected factors that propelled stocks higher, such as inflation staying unexpectedly tame.

“It was a surprise long-term interest rates stayed low,” Bittles said. “There would have been much stiffer competition for stocks if interest rates went to 3 percent as expected.”

As for where the next pop in the market will be, Wall Street is looking overseas.

Fears about the breakup of the European Union have stabilized and the continent has also delivered stronger economic data and profits, notes Quincy Krosby, market strategist at Prudential Financial, told The Post.