It is consequently heartening that Mr. Kim coupled his latest threats with an offer to open a dialogue with South Korea — an opening quickly seized by the South's president, Moon Jae-in. On Wednesday a hotline between the two governments was reopened for the first time in nearly two years, and face-to-face talks could begin next week. There are plenty of risks in this diplomacy and little chance that it will lead to a permanent solution to the crisis caused by the Kim regime's reckless pursuit of nuclear weapons. But it should be welcomed as a chance to reduce tensions and prevent a slide toward war.
Mr. Kim's overture did not surprise some Korea experts, as it came just weeks before the South is due to host the Winter Olympics. Mr. Kim offered to discuss the participation of a few of the North's athletes, something Mr. Moon had proposed. The regime's past practice has been to demand economic or political concessions in exchange for such cooperation, so it won't be surprising if it does so in this case. At a minimum, the North will probably seek the postponement of U.S.-South Korea military exercises during the games.
In that sense, the most obvious risk is that Mr. Kim will seek to use the talks to drive a wedge between the dovish Mr. Moon and Mr. Trump. Mr. Moon, clearly aware of that possibility, said Tuesday that any improvement of North-South relations must be linked to "resolving North Korea's nuclear program."
In truth, it is most unlikely that the Kim regime will agree anytime soon to give up its nuclear weapons or even seriously discuss that possibility. Ultimately, the elimination of the North Korean threat will probably require regime change, which the United States should seek to promote by nonmilitary means. But diplomacy could lower tensions and perhaps eventually advance some important interim measures such as a freeze on further nuclear and missile testing by Pyongyang.
That's why the Trump administration is wrong to treat the new dialogue skeptically, as the State Department did this week, or to reject anything short of maximal results, as did U.S. Ambassador to the United Nations Nikki Haley, who said "we won't take any of the talks seriously if they don't do something to ban all nuclear weapons in North Korea." The best approach is to keep seeking to raise the pressure on the Kim regime through sanctions and other economic pressures, while encouraging short-term deals to lower tensions — and avoiding pointless provocations. Before his reckless tweet about his "Button," Mr. Trump struck a more appropriate note: "Perhaps that is good news, perhaps not — we will see!"
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