The election of the left-leaning Moon Jae-in is a confidence booster for South Korea, in terms of both the country's democratic process and the prospects for fighting endemic corruption. But it took only four days for North Korea to test an intermediate-range ballistic missile following Moon's election. The launch serves as a reminder that despite the new administration's aspirations to promote peace and reconciliation, foreign policy is likely to be the biggest challenge of Moon's presidency.
Seoul faces an increasingly insecure Northeast Asia and must cope with the uncertainty of the Donald Trump administration.
The enduring tension that shapes South Korea's foreign policy is the desire for autonomy versus the necessity of the alliance with the U.S. -- an alliance that has prevented war and enabled regional prosperity for over six decades. South Korea's power shift from a conservative to a progressive leadership will tip the scale further toward autonomy, on the template of Moon's liberal predecessor, Roh Moo-hyun.
Moon wants to revitalize inter-Korean dialogue, renew economic cooperation, reclaim South Korea's responsibility for wartime decision-making from the U.S., and resume six-party talks on North Korea's denuclearization. But even though some of Moon's advisers desire greater independence from the U.S., there is no viable alternative that can guarantee South Korea's security.
Trump and Moon will face a number of flashpoints in their relationship: the goal of denuclearizing North Korea; the sharing of costs and responsibilities within the Washington-Seoul alliance; trade relations and the possible revision of the Korea-U.S. Free Trade Agreement, known as KORUS; and how to improve South Korea's relations with Japan.
STICKS OR CARROTS? The nub of the North Korea issue is how most effectively to achieve denuclearization. The Trump administration expects to dial up international pressure on Pyongyang as needed by convincing China to tighten the screws economically, while admitting the eventual need for negotiations. But Moon has expressed his preference for early negotiations and his desire to reopen the joint Kaesong Industrial Complex, which was closed by the conservative Park Geun-hye administration in February 2016 after North Korea's fourth nuclear test. A coordinated strategy will be essential: Conflict here would strain the alliance and drain American congressional and public support for South Korea.
Following North Korea's missile test in early March, the U.S. hurriedly deployed the Terminal High Altitude Area Defense, or THAAD, anti-ballistic missile system in South Korea's Seongju County. And although Trump's demand in late April that South Korea pay for THAAD probably boosted support for Moon prior to the election, publicly airing such unilateral demands will politicize the alliance and undermine local support for U.S. Forces Korea.
Trump's comments have created a pretext for THAAD critics within the Moon administration to investigate Park's decision to deploy the system, even though South Koreans strongly supported the move. That support could erode if Park administration officials are deemed to have exceeded their power within the acting government during the impeachment.
As for KORUS, Moon advisers proudly point to it as a trade deal the Roh government originally negotiated with the George W. Bush administration in 2007. The Barack Obama administration later ratified an "improved" version of the agreement. Now, Trump's obsession with a swelling merchandise trade deficit ignores that the U.S. enjoys a growing surplus in exports of services to South Korea, and that KORUS has fostered high-quality, job-creating inward investment from South Korea in the automobile and electronics sectors, among others.
And then there is the Japan problem. An additional source of friction between the Trump and Moon administrations could arise if South Korea tries to renegotiate the December 2015 deal over World War II "comfort women" with Japan. The agreement included an apology from the Japanese prime minister to Korean victims, and a nearly $9 million donation to a South Korean government-run foundation that supports the women and their families.
Moon supporters would claim the 2015 agreement did not satisfy Korean public expectations for Japan's formal expression of remorse, but Tokyo is unlikely to renegotiate. Regardless of how Japan-South Korea bilateral relations move forward, the U.S. will continue to see trilateral coordination with the Asian neighbors as essential for an effective pressure strategy against North Korea.
Moon's efforts to strengthen his country's diplomatic leadership within the alliance is likely to conflict with Trump's "America first" approach to alliances. Rather than a divergence of interests, the great risk to coordination between Trump and Moon is bad chemistry.
If mishandled, the collision of these forces could endanger the alliance, just at the moment when the world needs maximum coordination to bring North Korea's growing nuclear threat to heel.
Scott Snyder, senior fellow for Korea Studies at the Council on Foreign Relations, is author of the forthcoming book, "South Korea at the Crossroads: Autonomy and Alliance in an Era of Rival Powers" (Columbia University Press).