When President Donald Trump tweeted that “business is looking better than ever,” adding that “that just doesn’t happen,” Jim Cramer took the leader of the free world up on his claim.

“Business is looking better than ever with business enthusiasm at record levels. Stock Market at an all-time high. That doesn’t just happen!” Trump wrote.

“It’s worth pondering the question: Is the president right?” the “Mad Money” host said. “The short answer: Yes. At least about the market, he’s right. I say that because I’ve always been of the exact same mindset as the president: it doesn’t just happen. It takes a very special set of circumstances to have a market be this strong.”

But Cramer values skepticism and acknowledged that stocks are trading at historically pricey levels, giving more bearish investors cause to worry about overvaluation.

To clear the air, the “Mad Money” host decided to look at the Dow Jones Industrial Average’s 10 top-performing stocks in 2017 to see if their valuations are justified or overblown.

Up 52 percent year-to-date, the stock of aircraft giant Boeing has rallied on a strong order book and growth in airline traffic, which has increased demand from many of Boeing’s customers.

“The airlines have never been this flush. They’re lining up for planes. Airline traffic is in secular growth mode because of the great middle-class-ification occurring all over the globe. In short, [the move is] merited,” Cramer said.

If Apple were just a mobile phone company, Cramer would balk at its 35 percent run in 2017. But given the fact that the tech giant is, at its core, a consumer products company, Cramer said its valuation is actually still too cheap.

“Apple trades at 14 times earnings versus Clorox. Now, is that ridiculous? Even though its products are every bit as beloved as bleach?” Cramer said, comparing it to Clorox’s 23-times-earnings valuation. “Not only does Apple’s move up make sense, doesn’t it seem like it should be much higher?”

With several tailwinds at its back including accelerating growth and the global paper-to-plastic payment shift, Visa’s stock has enjoyed a 29 percent run since the start of the year.

The only potential threat to Visa is that the company hopes to take China by storm, and if Trump puts sanctions on China, Chinese officials could retaliate against U.S. companies like Visa.

“That would knock a great growth component from what I’m looking for and the stock would go lower. But at that point, you know what you’d be getting? Yes, a buying opportunity,” the “Mad Money” host said.

Having rallied 28 percent year-to-date, McDonald’s 6 percent worldwide growth is impressive for a company as old as established as the popular fast food chain, Cramer said.

“However, with a weaker dollar that translates to higher earnings, new technology that’s improving the experience and the simplified menu … the darned turn is just getting stronger,” he said. “It deserves the run.”

Up 22 percent for 2017, the construction giant has undergone a restructuring of late, laying off employees to right-size the organization and make it profitable again.

“With only a little bit of pick-up in revenues, [Caterpillar] can make a ton of money at the bottom line, and it did so this past quarter. Yet its sales are nowhere near back to where they were before the Great Recession,” Cramer said. “If that ever happens, this stock could easily vault 50 percent, maybe even more. You want CAT to come down, and come down now.”

Cramer said UnitedHealth‘s stock has rallied over 20 percent year to date thanks in large part to Congress’ inability to pass health care, making it the Dow’s token “Trump stock,” in Cramer’s eyes.

“If you believe Obamacare’s collapsing like the president, then you’ve got to own this stock,” the “Mad Money” host said. “I, along with just about everyone else I know, want to buy this stock cheaper than it is. Forget about it.”

Riding the wave of a clothing retail comeback, Nike’s stock has seen a 19 percent run so far in 2017, and after a strong quarterly report, Cramer thinks this is just the beginning of its rally.

Wal-Mart’s 17 percent gain makes sense to Cramer, who sees the low-cost retail giant as one of Amazon’s few worthy opponents.

“That’s why its stock’s been among the best performers in the market. The company, under CEO Doug McMillon, has made so many improvements and it’s going to leverage its huge store base to try to defeat Amazon,” Cramer said. “If I’m right, there’s no way this stock will stay this low.”

After reporting a strong quarter with accelerating growth in the cloud and cash generation galore, Microsoft’s stock should have run more than 16 percent for the year, Cramer said.

“Frankly, that’s just not enough after that remarkable quarter,” the “Mad Money” host said. “How is it possible that Microsoft’s stock hasn’t moved up more? That is the real question.”

American Express’ stock is the only one in the top 10 that Cramer hesitated to defend after a moderate, not great, quarter. But having seen the stock run as it has after similar earnings reports, he gave the credit card giant a pass.

“So let me give you the bottom line: on a case by case basis, which is what we do in Cramerica, I think the president’s right — this market’s doing amazing things. Whatever else you might think of Trump, his assessment of this market is accurate, and if you disagree, what can I say? You know nothing!” Cramer said. “I’ll just put it this way. It’s not hard to imagine these stocks going higher. It’s also relatively easy to argue that almost every single one of them is worth owning right here, and certainly on any dip. What more could you ask for?”

Disclosure: Cramer’s charitable trust owns shares of Apple.

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