Tokyo — President Trump is in Japan for high-stakes talks about trade with the U.S. and other key issues. Air Force One landed in Tokyo on Saturday, the start of a four-day visit for Mr. Trump and first lady Melania Trump.

For all the smiles, there is a deep uneasiness between the U.S. and Japan after the president threatened to impose stiff tariffs on Japanese cars and parts. The trip marks Mr. Trump's second visit to Japan since taking office, and the country is once again rolling out the red carpet.

On Saturday, the president met with high profile Japanese business executives, and on Monday, Mr. Trump will be the first world leader to meet Emperor Naruhito, who was installed last month after his father abdicated the throne due to old age.

Japanese Prime Minister Shinzo Abe has gone out of his way to woo Mr. Trump. A senior administration official said Mr. Trump and Abe have now met or spoken more than 40 times.

President Trump and first lady Melania Trump arrive at Haneda International Airport on May 25, 2019 in Tokyo. Koji Sasahara/Pool via Getty

The prime minister caters to the president's preferences. After a likely golf outing Sunday, the two leaders are expected to dine on hamburgers, and at a sumo wrestling match this weekend, Mr. Trump will be handing out a so-called "Trump trophy" to the winner.

There's also business to discuss, the president said military and trade issues are on the agenda, which could include Japan agreeing to buy more American military hardware, including F-35 fighter jets.

But it's a potential military conflict in the middle east that has the president's attention.

The Pentagon announced Friday that it would send an additional 900 troops to beef up defenses after blaming Iran for recent attacks. The U.S. has also deployed B-52 bombers and an aircraft carrier to the region.

The Trump administration is declaring an emergency over Iran and said it will now sell more arms to Saudi Arabia, a move congress had previously blocked. Mr. Trump thinks Iran gets the message.

"Right now, I don't think Iran wants to fight, and I certainly don't think they want to fight with us," Mr. Trump said before departing for his trip.

Of course, it is Memorial Day weekend, and Mr. Trump plans to visit a U.S. Naval base in Japan on Tuesday to greet troops before heading back home.