Was President Donald Trump's meeting with Chairman Kim Jong Un at the North-South border on June 30 a "legendary day, a very historic day" as Trump claimed afterward? To answer, we have to look at some things that did NOT happen, as well as speculate about their actual discussion.

[KCNA/Kyodo]

Here is what did NOT happen:

-- National Security Adviser John Bolton did not attend, instead making a side trip to Mongolia. As the most hawkish adviser to the president, he has made himself unwelcome to the North Koreans.

-- Trump did not speak extensively about completing the task of "denuclearization" and building a durable peace regime, an indication that he may be adopting a more realistic view of what can be accomplished with the DPRK (Democratic People's Republic of Korea) in the next year.

-- There was none of the war-like rhetoric that the two leaders exchanged throughout 2017. Trump blamed the media for not reporting that his efforts had drawn the two sides back from the brink of war, but of course did not speak about how his own words had brought us to the brink of conflict.

These are encouraging signs.

The only indication of what they did discuss is the president's statement that he and Kim had agreed to designate negotiators to resume talks in the next few weeks, a long overdue step. What is unclear is whether Trump made clear to Kim that the U.S. envoy, Stephen Biegun, enjoys the full confidence of the president. If he didn't do that, the North Koreans will continue to avoid serious negotiations with Biegun in hopes of resolving issues directly with the U.S. president.

The most important unknown is whether Trump is prepared to have those negotiators pursue reciprocal, step-for-step modest actions rather than the "big-for-big" deal Bolton has long advocated. There still exists room for limited agreements that constrain the DPRK's nuclear arsenal, while at the same time taking steps to build a "peace regime" on the Korean Peninsula, as the DPRK wishes, both of which will build the mutual confidence needed to take the more difficult steps.

(Thomas Countryman speaks in an interview in Washington on Nov. 30, 2017.)

Biegun and his counterpart could start by discussing:

-- A codification of the freeze on nuclear testing, including the DPRK signing the Comprehensive Test Ban Treaty, and of ballistic missiles;

-- A verifiable halt to production of fissile material (plutonium and highly enriched uranium), including cessation of activity at the Yongbyon complex;

-- A declaration of the DPRK's fissile material stock;

-- An affirmation by the U.S. that the Korean War is over, and that the U.S. has no hostile intention toward the DPRK;

-- Limited sanctions relief (beginning with U.S. bilateral sanctions) in proportion to the significance of the steps taken by the North.

This more limited agenda would further reduce the risk of regional conflict, and would also reinforce the Seoul-Pyongyang process of rapprochement, which is an important underpinning to the U.S. efforts. Most importantly, a gradual, less ambitious process is more realistic given the limited time before the U.S. election.

Two other things that haven't changed after this meeting:

-- North Korea still has a nuclear arsenal, and even a little more fissile material than it had before the Singapore summit.

-- The U.S. and the rest of the world are still imposing strong economic sanctions on the DPRK, even a little stronger than they were before the Singapore summit.

A realistic and phased approach, conducted by empowered negotiators, offers the hope of achieving the goals both leaders say they share: denuclearization on the Korean Peninsula, and a permanent state of peace. If at the June 30 meeting the two leaders pointed their teams in that new direction, it will be remembered as a historic turning point.

(Thomas Countryman is former acting undersecretary of state for arms control and international security.)