The problem is compounded by two additional issues. The first is the absence of a proactive policy agenda in the current alliance relationship. At the beginning of 2019 and embarking on the third year of the Trump presidency, one is hard-pressed to delineate what the issues are that constitute the mainstay of the proactive alliance development outside of North Korea. Good alliance maintenance does not equate with merely maintaining the status quo, but with continuing to find new areas of cooperation to make the alliance better. This is absent today. By comparison, the last time there was a politically progressive government in Korea, a multitude of “alliance advancement” projects were being worked on in addition to North Korea. These included Yongsan base relocation, NATO+3 status for South Korean arms purchases, a visa waiver program, KORUS, action on climate change, troop deployments in Iraq and provincial reconstruction teams in Afghanistan. All of these contributed to a positive and forward-looking agenda for the alliance that reflected both countries’ interests. Today, the alliance is entirely dominated by tension over North Korea, trade and the cost-sharing negotiations (Special Measures Agreement) in which Trump wants South Korea to pay entirely for the U.S. troop presence on the peninsula.

The second source for Trump’s dismissal of the alliance’s importance is a general lack of knowledge in the administration about the history of the alliance. Officials have a cross-sectional rather than longitudinal view of policies. The present government in Seoul is the first progressive one in nine years that may naturally want to take a different policy path on North Korea based on their perceived policy neglect of previous conservative governments. This path may succeed or fail, and that judgment will be rendered not by the Moon government but by the public in forthcoming elections. That is what we should expect from democratic allies like South Korea who have consistently been a loyal U.S. partner on the Korean Peninsula and around the world, fighting with the United States in every war since the Korean War. But Trump officials instead simplistically view the current government as “too progressive,” in bed with the North, not worthy of trust and ultimately not a good ally. And if one does not value an ally, then there is no reason to expend time, energy and resources there.

Could the U.S. president be stopped from withdrawing from Korea? The answer is that there is very little standing in his way. As the commander-in-chief, the president exercises final and unchallenged say over military matters. Congress could pass resolutions trying to restrain the president, and, in the case of South Korea, this past year has passed the Asia Reassurance Initiative Act calling on the United States to develop a long-term strategic vision for the Indo-Pacific region, including reiterating our commitment to the Mutual Defense Treaty between the United States and the ROK and strengthening our alliance, as well as amendments to the National Defense Authorization Act. But for Congress to execute an effort to block the commander-in-chief from altering troop deployments in a time of peace would take the United States into uncharted waters and foment a constitutional crisis. Finally, history has shown little compunction by past U.S. presidents, let alone Trump, to alter troop deployments unilaterally without consultation with allies. Richard Nixon pulled out one division from South Korea as part of the Guam Doctrine in 1971 even as South Korean troops constituted the second largest warfighting contingent in Vietnam. Carter considered a total withdrawal of forces from South Korea in 1977 without consulting Seoul. And during the Iraq War in 2003, the United States rotated forces off the Korean peninsula to the Middle East. If Trump withdrew troops, he would certainly not be the first U.S. president to act unilaterally.

THE IMPLICATIONS of a Trump pullout from Korea are unknown but would almost certainly have initially negative repercussions. The benefits of a peace agreement and the positive atmospherics of U.S.-DPRK summits (and Trump’s promise to Kim to build “beachfront” condos in the North) would be offset by the security deficits incurred by a suboptimal denuclearization deal that leaves capabilities intact (albeit possibly capped), while the United States withdraws forces.

An American withdrawal would shock South Korea. It would set off domestic turmoil as conservatives would attack progressives for losing America. Others would claim long-sought Korean independence from the U.S. yoke. After the initial perturbations, the alliance could conceivably survive a Trump pullout. The United States might maintain a nominal security commitment to South Korea without the traditional physical tripwire presence. The shock of a withdrawal might spark the alliance to innovate on a more even footing, including a transfer of wartime operational command, more autonomous ROK defense spending and the replacement of an integrated command structure with coordinated defense guidelines between the two militaries, not unlike the U.S.-Japan alliance. But the credibility of the U.S. security commitment would almost certainly weaken in Korean and American eyes.

The real cost could come in the longer-term U.S. strategy in Asia. In addition to a Trump pullout roiling the kospi, Nikkei and Shanghai composite indexes, possibly leading to some capital flight from the region, the willingness of the United States to withdraw prematurely from the Korean Peninsula would create a crisis of confidence among U.S. allies and partners, including Japan, Australia and Taiwan which would feed self-help inclinations in all capitals. By leaving a frontline Cold War state, a U.S. withdrawal would give confidence to China that it has achieved a watershed success in its long-term strategic objective to remove the United States from Asia. This would enhance Chinese confidence in picking apart the U.S. alliance system with economic domination of the Korean Peninsula and the political alienation of Japan. Beijing would also pressure Taiwan, which itself would be experiencing a crisis of confidence in U.S. commitments. By leaving South Korea, the United States would effectively be returning to a historical geostrategic orientation off of continental Asia, effectively ceding to a Chinese sphere of influence while maintaining a maritime position not unlike what George Kennan suggested of the United States after World War II and before the North Korean invasion in 1950. However, the difference is that Kennan’s view of a Chinese-dominated continental Asia was non-threatening given the absence of power projection capabilities. Today, a continental Asia dominated by China with Taiwan in tow would have major force projection implications for diminished American power and presence in Asia.

The policy implications of this analysis for the United States and its allies have several dimensions. First, future negotiations with North Korea, all the way up to the summit level, must be guided by the core principle of preservation of alliance equities. Denuclearization may require the lifting of sanctions, the establishment of political offices, negative security assurances and economic/energy assistance, but the United States should not play willy-nilly with alliance capabilities, including troop deployments, their force posture and their readiness. Second, while a peace agreement is desirous in terms of changing the environment surrounding the Korean Peninsula, negotiations over such an agreement should not carry explicit nor implicit promises about changing the disposition of forces on the Peninsula. Third, through legislation, Congress must continue to maintain oversight and budgetary authority over changes of the force levels in South Korea. Fourth, any decision to draw down or pullout forces must be subject to an interagency and congressional review of the consequences—both positive and negative—of such a decision. Fifth, the intelligence community must carry out a broad national estimate of the impact on peninsular and regional security of such a plan before any decision is finalized. Finally, while the disposition of U.S. troops aboard is not subject to the approval of host nations, the United States should consult closely with regional allies about their views of the impact of such changes on security and credibility of the United States as the Asia-Pacific power most credited with maintaining stability and prosperity in the region.

Victor Cha is the D.S. Song-KF Professor of Government at Georgetown University, a Senior Adviser and Korea Chair at the Center for Strategic and International Studies, a Senior Adviser at the George W. Bush Institute, and a MSNBC News Contributor.

Image: Reuters