Secretary of State John F. Kerry says he will remain active on conflict resolution and confronting climate change when he leaves office. (Alex Brandon/AP)

John F. Kerry has already started referring to himself as Citizen Kerry.

After 29 years in the Senate, and four years as secretary of state, Kerry is about to return to private life in Boston. When he returns from a four-country trip late Wednesday, he will have traveled a record 1.4 million miles and spent cumulatively a year and half overseas on various diplomatic forays.

But after leaving office, some of the signature policies and accomplishments he is most proud of may be abandoned or subject to significant change. President-elect Donald Trump has suggested he will get tougher on Iran, work with Russia, treat climate change with some skepticism and change the approach to Syria and Israel.

[Kerry’s exit memo is filled with accomplishments Trump may want to undo]

Or maybe he won’t, Kerry suggests, brushing off suggestions the Obama’s administration’s legacy is about to be upended.

“I’ve been around long enough to see the difference between campaigning and governing, and I just don’t know yet what they will do,” he said in an interview in Paris on Sunday after joining diplomats from 70 countries to discuss resuscitating Israeli and Palestinian negotiations.

While declining to talk directly about Trump’s positions, Kerry urged the incoming administration not to take steps that would doom the 2015 Iran nuclear deal, which lifted sanctions against Iran in return for restrictions on its nuclear program. Trump has panned it, and Republicans in Congress have threatened to impose new sanctions.

[Iran nuclear deal may not survive a Trump administration]

“I would caution people very strongly against looking for excuses to stir it up or to not comply on our part. I think that would be very damaging to the credibility of the United States,” he said.

He was cautiously optimistic about prospects for peace talks over Syria. Russia has invited the Trump administration to join the talks it is sponsoring with Turkey and Iran later this month, after freezing out the Obama administration.

[First sign of enhanced U.S.-Russia relations under Trump: an invite to Syria talks]

“I’ve always believed that there was a moment where this would move into a slightly different phase,” he said. “And I think it could well be that that moment could be at hand – not necessarily, not definitively, but I do believe it could be.”

(Reuters)

Kerry leaves office at a time when the U.S.-Israeli relationship has been strained by the U.S. decision not to veto a U.N. Security Council resolution condemning Israeli settlements, as well as Palestinian incitement to violence. Prime Minister Benjamin Netanyahu, the leader Kerry has spent the most time on the phone with, has openly welcomed Trump getting sworn in.

Kerry said the U.N. resolution, and a speech he made defending it, was prompted by his conviction that the time for a two-state solution to the decades-old conflict is running out, and Israel has ignored U.S. entreaties to rein in settlement growth.

“But if our good friends are just not ready to listen to us when we say we’re having a harder and harder time defending you, it’s getting harder and harder in the international community to defend it, I think that it was really important for us to support our own policy,” he said.

“But I will stand up forever for the truth of the words I spoke about what is happening to Israel and about the choice Israel has.”

Among his main concerns for the future, he said, are the persistence of violent extremism, and North Korea’s nuclear weapons program under its mercurial leader Kim Jong-un.

The way to combat terrorism, he said, is by trying to prevent radicalization by providing more opportunities to young people lacking job prospects and education.

North Korea poses a threat “on a par” with radical extremism, Kerry said. Last year, the United Nations placed the country under the most severe set of sanctions ever. Kerry called for more pressure to be exerted on Pyongyang.

“I think that we’ve done well to get China to agree to several more stringent sanctions measures and to enforce them at the U.N.,” he said. “But we still also believe more has to be done, and we would support rational, thoughtful approaches by the new administration to try to continue what we’ve been doing, which is raising the level of pressure — and it needs to be raised more.”

Kerry showed no concern about filling a void when he wakes up Saturday morning with no urgent crises to address, no phone calls to world leaders to make, no stable of diplomats to direct.

He said he will remain involved with peace and conflict resolution, combatting climate change and the state of the oceans.

“I will miss trying to solve some of these problems very directly as someone who has these incredible resources and talented people to be able to try to do that with,” he said. “And so one of my challenges will be trying to land somewhere in some way that I still have talented people working with me and I’m able to work on some of those kinds of issues that I find rewarding and challenging at the same time.

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