North Korea will be high on the agenda during the U.N. General Assembly session in NY this coming week. He also had some tough talk for North Korea. He offered a spirited indictment of Kim Jong Un, the North Korean leader, not only for his nuclear and missile tests but also his mistreatment of the North Korean people and, of course, his fatal treatment of that American citizen who was held prisoner there for all those months.
Pyongyang has launched dozens of missiles as it accelerates a weapons program created to provide the ability to target the United States with a powerful, nuclear-tipped missile. Rocket Man is on a suicide mission for himself and for his regime. He urged United Nations member states to work together to isolate the Kim government until it ceases its "hostile" behavior.
Mr Trump has been a harsh critic of the United Nations, but with world leaders and foreign ministers, including Australia's Julie Bishop, looking on inside the UN's packed Economic and Social Council Chamber the president did soften his words.
Mr Trump's speech was also notable for its omissions.
"He missed an opportunity to present any positive actions the United Nations could take with respect to North Korea, and he launched a diatribe against Iran, again offering no pathway forward", Feinstein said.
However, the Korean Peninsula crisis should be solved through a political process, said UN Secretary-General Antonio Guterres in his debut address to the UN General Assembly, just minutes before Trump's remarks.More news: North Korea: UN trying to 'exterminate' us
"As President of the United States, I will defend America's interests above all else", he said.
"I don't think you've heard the last of it, believe me".
The address was a harsh rebuke of North Korea's ongoing nuclear weapons buildup.
Mr Trump's 40-minute speech, which was met by restrained applause in the chamber, also set out some broader principles of USA foreign policy as Mr Trump espoused the notion of national sovereignty, a common theme of his presidential campaign.
The president "has had a deeply developed world view for decades in terms of reshaping [and] establishing fairness in America's relationships with other countries", the White House official said.
During the reform session, Trump alluded to one of his eponymous properties, Trump World Tower, when he said he "saw great potential right across the street".