"With that in mind, the thought of sending troops into harm's way and expending resources on another potentially unwinnable war is chilling". He also singled out trade, which he said had been "badly handled" in the region for years.
But Kang warned that "we need to be very careful about military options", adding that they "are there to give strength to diplomacy". It was not pleasant for them, was it?' said Trump, who wore a leather bomber jacket as he addressed the troops.
North Korean leader Kim Jong-un attends a meeting with a committee of the Workers' Party of Korea about the test of a hydrogen bomb, at an unknown location, September 4, 2017.
North Korea's recent actions, including several missiles that overflew Japan and Pyongyang's sixth and largest nuclear test, have raised the stakes in the most critical worldwide challenge of Trump's presidency.
'We will never yield, never waver and never falter in defense of our freedom, ' Trump said. "We will not stand for that, the era of strategic patience is over".
Trump was due to arrive early Tuesday in Seoul - where the subject of how to tackle North Korea's totalitarian dictator is expected to be at the top of the agenda. The toll could be broad across the entire region, with millions presumed to die in South Korea alone, with Japan and Guam also likely to be targeted, and a "catastrophic" loss of USA troops participating in the war.
When playing out hypothetical war scenarios in case armed conflict were to break out, the Pentagon "estimated the potential number of dead in South Korea at 20,000 each day", retired general Rob Givens told the Los Angeles Times.
Meanwhile, South Korea has also begun tightening its measures against the Pyongyang by implementing sanctions against 18 North Koreans.
South Korea now pays more than 900 billion won ($800 million) annually and negotiations with the United States are to start in the coming months to try to determine a new amount for South Korea to contribute.
North Korea has said in public statements that it wants an official end to the Korean War. Trump has criticized the deal as a source of the US trade deficit with South Korea, an argument officials there dismiss.