Before the visit of United States President Donald Trump, there were fears that he would threaten to rain down fire and fury once more on North Korea.

But in South Korea last week, the unpredictable Mr Trump was praised instead for a "very presidential" speech in the Korean Parliament, which rallied global support in addressing North Korea's nuclear issue.

He was also lauded for showing sincerity in reaffirming American commitment to South Korea's defence and issuing a firm warning to the North.

Mr Trump even assured South Koreans that there will be "no skipping" their country when it comes to major decisions, easing in part fears of "Korea passing".

The term was coined by the local media to describe how Seoul fears being left out of important Washington decisions as Mr Trump and Japan Prime Minister Shinzo Abe bond over a love of golf.

But Mr Trump gave the assurance: "South Korea is very important to me, and there will be no skipping South Korea."

During his visit, he had also refrained from dialling up pressure on Seoul to reduce the trade deficit with the US or to take on more of the defence cost-sharing burden.

Mr Trump and South Korean President Moon Jae In agreed on the need for South Korea to strengthen its own defence against the North, and for South Korea to buy more military equipment from the US, which would in turn create jobs for Americans and reduce US trade deficit.

Still, some critics said Mr Trump fell short of offering a concrete solution to the nuclear stalemate. Questions remain on how North Korean leader Kim Jong Un can "come to the table and make a deal", as Mr Trump had suggested.

Professor Kim Jae Chun of Sogang University said that Mr Trump's visit was "quite successful", but both sides had a lot of homework to do to iron out remaining differences.

He also noted Mr Trump and his South Korean counterpart, Mr Moon, given their vastly different personalities and background, are unable to forge a friendship like the one between Mr Trump and Mr Abe.

"The two guys are not on the same page... Moon still harbours a suspicion that Trump might use military options without consulting him, while Trump is still worrying about Moon leaning towards dialogue abruptly."

Dr Go Myong Hyun of the Asan Institute for Policy Studies warned that Mr Trump's comments about not skipping South Korea could be merely "lip service".

"We know that if things get really heated and the US has to engage in preventive war against North Korea, they will do it without South Korea," he added.