I was walking to the National Press Building on Monday when a TV news crew stopped me and sought my comment on the upcoming summit between US President Donald Trump and the Democratic People's Republic of Korea leader Kim Jong-un.

They picked the right person since I am going to Singapore to cover the June 12 summit to be held at the Capella Sentosa Hotel. It will be a historic summit: The first one between a sitting US president and the top leader of the DPRK.

I applauded Trump in a column on May 20, 2016, after, the then presumptive Republican presidential candidate, said he would be willing to talk to Kim. "I would speak to him, I would have no problem speaking to him," Trump said at the time.

China has long called for direct engagement between the US and the DPRK, the two major players responsible for the tension on the Korea Peninsula. The Barack Obama administration rejected such direct diplomatic engagement despite its diplomatic advances with Iran and Cuba.

The Trump administration threatened a military strike following nuclear and missile tests by the DPRK. And the ensuing war of words between Trump and Kim early this year worried many in the region about a possible catastrophic conflict that would result in the loss of millions of lives.

Tension has been dramatically reduced since March when it was announced that Trump had accepted an invitation to meet Kim. Trump later canceled the planned meeting blaming Pyongyang, saying it had shown "tremendous anger and open hostility". But he revived it just eight days later after the DPRK called Trump's decision "regrettable" and held out hopes for "peace and stability".

Many in the US believe the summit will immediately result in complete, verifiable and irreversible denuclearization by the DPRK. That's why when Trump called the summit a "getting-to-know-you meeting," he drew sharp criticism within the US.

But his lowering of expectations is actually realistic. Given the decades of hostility between the two countries, which are technically still at war with each other following a 1953 armistice, there has been very little mutual understanding and mutual trust between the two countries. It is unrealistic to expect that an issue as difficult and complicated as denuclearization of the Korean Peninsula, which the US seeks, and the security guarantee from the US, which the DPRK has demanded in return, will materialize during the upcoming meeting.

Back in the 1970s following the ice-breaking trip to China by US President Richard Nixon in 1972, it took many years for China and the US just to normalize their relations. China-US relations have become broader and deeper in the past decades thanks to the engagement pursued by both sides. This is despite their differences on a range of issues.

Rome was not built in a day. The denuclearization of the Korean Peninsula and the reconciliation between the US and the DPRK will not be accomplished in one single meeting. Even US experts have cautioned that the denuclearization process itself could take as long as 15 years.

What it means is that the two sides should continue to actively engage diplomatically and meet each other halfway, and refrain from returning to the past war of words and exchange of military threats.

If the Trump-Kim summit in Sentosa, meaning "peace and tranquility" in Malay, can be the beginning of that peace and reconciliation process, it will be not only a historic summit but also a successful one.

The author is deputy editor of China Daily USA.