Briefly visiting reporters in the press cabin shortly after takeoff, Trump reaffirmed his remarks early Friday as he departed the White House, in which he said he planned to extend his trip by a day, to attend the East Asia Summit (EAS) in the Philippines.
"We're staying an extra day, because the following day is actually the most important day," the president said, when asked about his abrupt and unexpected change in plans.
President Trump?s five-country tour of Asia
Although Trump had always planned to attend the Association of Southeast Asian Nations (ASEAN) summit in the Philippines, he initially expected to head back to Washington before the additional key Asia summit the following day, which includes all the ASEAN countries, as well as eight additional ones.
The decision not to attend had prompted much consternation in the region, which worried that Trump did not care about Southeast Asia.
After a nearly 10-hour flight, during which the president tweeted four times, Trump emerged from his plane buoyed, shaking hands with well-wishers on the tarmac for about 15 minutes, before heading to U.S. Pacific Command for a briefing.
"I tell you: This is very special being in Hawaii," he said.
The president also seemed genuinely excited about his planned evening visit to Pearl Harbor, which, he said, "I've read about, spoken about, heard about, studied, but I haven't seen. And that is going to be very exciting for me."
Not everyone was as enthusiastic about Trump's visit as he was. Democrats completely dominate Hawaii's Senate, just five Republicans hold office in the state's 51-seat House, and Trump won just 29 percent of the vote here in the 2016 presidential election.
On Friday, hundreds of protesters showed up at the Hawaii State Capitol — a much larger turnout than at most local demonstrations here. Many said they were frustrated by Trump's entry ban, especially because Hawaii is the most diverse state in the nation and has a large immigrant population.
"I have no aloha for him and I don't think the state of Hawaii does either," said protester Laura Margulies, who held a sign that read "No Aloha 4 Trump."
Among the crowd of protesters — banging drums, dancing and honking horns — was a cardboard cutout of former president Barack Obama, donning a University of Hawaii baseball cap.
Davey Strand, a Hawaii Democrat who brought the sign, said his wife was born in the same hospital as Obama.
Trump fanned the flames of birtherism, even publicly saying he had sent private investigators to the state to search for Obama's birth certificate, and Strand called Trump's false claims that the former president wasn't born in United States "insulting."
Obama is the state's "precious local boy," said protester Susan Bruhl. It was frustrating to watch Trump try to undo the Obama administration's work, she said.
But Trump, whose motorcade passed only streets of almost entirely supportive residents, did not seem to be aware of the protests, nor did they dampen his zest for making the most of his layover.
The president finally arrived at Pearl Harbor at dusk, as the sun turned orange and slid low, and boarded a barge for a brief and somber visit to the USS Arizona Memorial, which commemorates the 1,177 service members who died in the Dec. 7, 1941, attack.
Accompanied by his wife, Melania, the president took in the nearly all-white shrine — which sits atop the sunken wreck of the USS Arizona — and presided over a wreath-laying ceremony before a marble wall etched with the names of those who perished.
Then, the Trumps threw large white pikake flower petals into the waters below, peering down as they drifted away.
The White House had briefly signaled that Trump might make remarks at Pearl Harbor — perhaps an early version of the bellicose speech he is expected to deliver during his trip, aimed at North Korea — but he was restrained and respectful, largely listening and taking in the memorial.
For at least one day, the saber-rattling could wait.
Courtney Teague contributed to this report.