North Korea will denuclearize, President Kim Jong Un.
Stephanopoulos asked how Trump could trust the brutal dictator.
"I do trust him, yeah," Trump said. "Maybe in a year you’ll be interviewing and I'll say I made a mistake. It's possible. We’re dealing at a high level, a lot of things can change a lot of things are possible."
He pressed the president on his previous criticism of North Korea's human rights abuses including starving his people, running labor camps and assassinating members of his own family.
"George, I'm given what I'm given," Trump said. "This is what we have, this is where we are, and I can only tell you from my experience, and I’ve met him, I've spoken with him. I’ve met him. And this is, this has started early and it's been very intense. I think that he really wants to do a great job for North Korea. I think he wants to de-nuke, without that, there's nothing to discuss. It was on the table from the beginning, and you see a total denuclearization of North Korea – so important."
Trump talked about the agreements that were reached at the summit in Singapore today, saying that he believes the North Korean leader "wants to do the right thing".
"We have the framework for getting ready to denuclearize," Trump said. "He's de-nuking the whole place. I think he's going to start now."
Trump seemed to hold an optimistic take on Kim's intentions, saying that the dictator "really wants to do something I think terrific for their country."
When asked if there was talk of pulling U.S. troops out of South Korea, Trump said the topic didn't come up.
"We didn't discuss that, no. We're not going to play the war games... I thought they were very provocative. I also they're also very expensive," Trump said.
Another potential sticking point that didn't come up? The nuclear umbrella that the U.S. has over South Korea, that is intended to protect it from any missile strikes from the North.
When asked by Stephanopoulos if the removal of the nuclear umbrella was "on the table," Trump said no, saying the umbrella had not even been discussed.
(MORE: Kim Jong Un, Trump participate in signing ceremony, make history: Live updates) (MORE: From 'fire and fury' to 'rocket man,' the various barbs traded between Trump and Kim Jong Un) (MORE: Trump lavishes Kim Jong Un with praise following historic summit)Trump pointed to the international partners that he plans to work with in the pursuit of a denuclearized North Korea, pointing to South Korea, Japan, and China as countries that he plans to work with moving forward. An underlying strain of Trump's takeaways from the interview was Kim's perceived willingness to do the right thing.
"Over my lifetime I've done a lot of deals with a lot of people and sometimes the people you most distrust turn out to be the most honorable ones and the people that you do trust turn out to be not the honorable ones," Trump said.
"I believe he wants to get it done."
Trump suggested there could be another meeting of the two leaders in the future and that he would like to hold a gathering at the White House.
"I would love to have him at the White House. Whatever it takes," Trump said.
Trump arrived in Singapore on Sunday evening local time, fresh off of the G-7 summit in Quebec having angered American allies over his administration's move to impose steep tariffs on aluminum and steel imports from the European Union, Mexico and Canada. Trump backed out of a joint communique with other G-7 countries that acknowledged "free, fair, and mutually beneficial trade is a key engine for growth and jobs."
Trump rescinded his endorsement after Canadian Prime Minister Justin Trudeau held a news conference saying all seven countries had signed the communique despite "some strong, firm conversations on trade, and specifically American tariffs."
Trudeau said he informed Trump that Canadians "who stood shoulder-to-shoulder with American soldiers in far-off lands" do not take lightly the idea that the tariffs are for national-security reasons.
"It's kind of insulting," Trudeau said.
In his interview with Stephanopoulos, Trump talked about the tension, saying "I actually like Justin" but calling the tariff disagreement "a mistake."
"Everybody was happy" at the end of the G-7 conference, Trump said. "And then he [Trudeau] gave out a little bit of an obnoxious thing. I actually like Justin, I think he’s good. I like him but he shouldn't have done that. That was a mistake, that’s going to cost him a lot of money," Trump said today.
Trump, who is known for needing little sleep, told Stephanopoulos that even for him, this has been an "intense" week.
"I've been up 24 hours now straight between phone calls and working it," he said. "This is a very, look this is 72 years we’re talking about, and we put it into one very intensive day and some meetings beforehand."
The meeting in Singapore marked the first time a sitting U.S. president met face-to-face with a North Korean leader, but it almost didn't happen.
Only two weeks ago, Trump canceled the meeting, citing "open hostility" from North Korea. But after some last-minute diplomacy, the meeting was scheduled again and took place Tuesday at 9 a.m. Singapore time, at the exclusive Capella hotel on the secluded – and secure – resort island of Sentosa.
Trump entered the meeting confident, boasting during the buildup that he expected to “have a great discussion.”
"I feel really great," Trump said just moments before the historic meeting. "We're going to have a great discussion, I think, a tremendous success, this will be tremendously successful. It's my honor and we will have a terrific relationship I have no doubt."
Kim smiled as the translator interpreted Trump’s comments, before issuing a brief statement of his own.
"It was not an easy path here," Kim said. "There's a history of holding onto our ankles, and it appeared there were times that there were unfortunate practices where they were trying to block our eyes and our ears, but we've overcome everything and come to this place."
Their first meeting this morning was one-on-one, with only the two leaders and their translators meeting for about 45 minutes. Trump told reporters that his one-on-one with Kim had been “very, very good” and said the two have an “excellent relationship.” Kim did not respond to shouted questions about whether he will give up his country's nuclear weapons.
The two then sat down with their broader national security delegations for a second meeting at the Capella Hotel resort on Sentosa Island. The president was joined by a translator and his chief of staff John Kelly along with Secretary Mike Pompeo and National Security Adviser John Bolton.
Trump gave some insights into his conversations with Kim and how the relationship between the U.S. and North Korea soured in the past.
He said that Kim described being "let down by the United States" in the past, though Trump brushed it aside saying "but that's irrelevant."
The president said that his newly formed relationship with the dictator is markedly different from the lesser relationships his predecessors had with Kim's relatives, saying "they've never gone this far, you know, they've never been at a level like this, and his father never dealt with a president."
And in Trump's mind, that could be a game changer.
"This is different, I believe you’ll find in the years to come, George. I think you’re going to find this different," Trump said.