Trump and his wife Melania tossed flower petals into the waters of the USS Arizona memorial, later taking part in a wreath-laying ceremony to honour soldiers who died in a Japanese surprise attack in 1941 that triggered the US entry into World War II.
And with the belligerent regime in Pyongyang threatening to "sink" Japan into the sea, the sense of tension and anxiety has left many ethnic Koreans feeling conflicted - especially the younger generation for whom modern Japan is the only home they have known. It's a big problem for our country and for the world, and we want to get it solved. Trump is expected to go to the Forbidden City and participate in an inspection of Chinese troops, though China has released few other details. Trump landed at Yokota Air Base on the outskirts of Tokyo, where he will begin his trip with an address to American servicemembers.
"I'm not very worried about Trump putting South Korea in danger", said Beak Yong-cham, 60, who said he was a veteran of the Republic of Korea Marine Corps.
He said welcoming a guest hospitably is a tradition that has been handed down from generation to generation in South Korea, adding that through the hospitability, South Korea and the United States will be able to confirm the firm alliance.
Pavlovsky did admit, though, he was not sure how much of a role Putin played in the social media and espionage tactics used to meddle in the U.S. election last year.
"It is grueling, they tell me", he said.
It's unclear what the "plus" means.
Thousands of South Koreans protested Sunday against an upcoming visit by Donald Trump and called for peace as the US President begins an Asian tour dominated by North Korea's nuclear programme.
Thirteen days, five countries - it's a grueling schedule for President Trump and his staff.
It will be the longest tour of Asia by a US president in 25 years. Trump and Putin previously met along the sidelines of a summit in Europe this summer.
But Seoul expects Pyongyang will detonate more devices as it continues its efforts to attach a nuclear warhead to a ballistic rocket. A far older crowd, many wearing military uniforms, could be seen waving American flags and signs that said "Welcome Trump". I don't know who believed in America that Putin elected Trump, but Putin believed that.
"The two sides have subtle differences in their positions", said Kim Hyun-Wook, a professor at the Korea National Diplomatic Academy.
President Trump's first trip overseas in May was another long haul.
But Trump has demonstrated cordial relations with Xi and has struck up a friendship with Abe. The White House said the president would stress "the importance of fair and reciprocal economic ties with America's trade partners".