Donald Trump made his best case yet for his presidential candidacy Thursday. In a speech to the New York Economic Club, he tamped down on needless populism and zeroed in on the No. 1 issue affecting Americans: the anemic Obama economy and Hillary Clinton’s bizarre embrace of the policies that caused it.

Now, if he can only give a variation of that speech every day until Election Day.

Voters have “trustworthiness” issues with both candidates. But when you drill down on what Americans care most about, it’s the economy. And this is where Hillary is possibly at her weakest, supporting and at times promising to expand upon the policies that have given the country low growth, massive under-employment and putrid wage growth for the vast middle class.

Yes, Trump was light on the specifics of how he was going to pay for some of his promises, like child-tax credits and infrastructure investments. And of course no Trump address on the economy would be complete without an obligatory and nonsensical attack on free trade — sure enough he mentioned a possible trade war with China and how he’ll renegotiate NAFTA.

Luckily, he kept much of his trade nonsense to a minimum, and instead offered a stirring, largely Reaganesque vision of America’s economic future where he would cut taxes ($4.4 trillion of them) and simplify the tax code (from seven to just three brackets).

He would also lower our onerous corporate tax rate to 15 percent, making the United States more competitive globally, and cut job-killing regulations that squeeze corporate profits and cost jobs.

It was a stark contrast to the policies of the past eight years, which Clinton vows to repeat and build upon.

“My opponent’s plan . . . offers only more taxing, regulating, more spending and more wealth redistribution — a future of slow growth, declining incomes and dwindling prosperity,” Trump said. “If we lower our taxes, remove destructive regulations, unleash the vast treasure of American energy and negotiate trade deals that put America first, then there is no limit to the number of jobs we can create and the amount of prosperity we can unleash . . . Instead of driving jobs and wealth away, America will become the world’s great magnet for innovation and job creation.”

He even took a swipe at the growing chorus of left-wing economists, like Bill Clinton’s former Treasury Secretary Larry Summers, who have tried to rationalize the current Obama slow-growth economy Clinton wants to accept as the “new normal,” or secular stagnation, that we should all get used to, rather than something produced by left-wing economic dogma that desperately needs to be thrown into the ash heap of history.

“My economic plan rejects the cynicism that says our labor force will keep declining, that our jobs will keep leaving and that our economy can never grow as it did once before,” Trump said.

He added: “We reject the pessimism that says our standard of living can no longer rise, and that all that’s left to do is divide up and redistribute our shrinking resources. Everything that is broken today can be fixed, and every failure can be turned into a great success.”

The politics behind Hillary Clinton’s Obamanomics embrace are obvious: She needs Obama’s help getting elected.

But now she’s forced to defend the indefensible — a point Trump drove home during his speech. Indeed, for every positive report about the Obama economy, like one earlier in the week showing a slight ebbing in income inequality, there are many more demonstrating that Americans still remain massively under-employed and have wages barely budging, as Trump explained.

And he did it with style, at one point quipping that “it used to be cars were made in Flint and you couldn’t drink the water in Mexico. Now, the cars are made in Mexico and you can’t drink the water in Flint” — a reference to the water crisis that engulfed the city that has come to symbolize how government these days is bloated and inefficient.

He couldn’t have said it better.

Charles Gasparino is a Fox Business Network senior correspondent.