Ending the Korean War

This post is authored by Shea Cotton 

The upcoming Trump-Kim summit in Hanoi has revived the prospect of formally ending the Korean War. Much of the ongoing conversation presents this possibility only in vague terms, or focuses on whether Trump should make some type of peace “declaration”. There has been a lot of discussion on this specific option recently and though it would not constitute a treaty, some statements from North Korea suggest this is all they are looking for. However, a declaration does not provide much if any legal guarantees to North Korea and there is nothing stopping the President (or a future President) from proclaiming different. If North Korea wants greater reassurances of peace, a proclamation could serve as a potential starting place setting the groundwork for future negotiations on a treaty.

Changing the current state of the Korean War in political or legal terms, but particularly the latter, is a complex task with immense significance for Korean Peninsula security issues and alliance relations. And many interested in the subject are understandably confused by the legal process for initiating such a change in the US system. So what, in general terms, does the spectrum of options look like for US policy-makers, and how could any approach be operationalized in the US system?

Unique Circumstances

Though not universally agreed upon (the North Koreans aren’t a huge fan, for example) the Vienna Convention on the Law of Treaties defines a treaty as “an international agreement concluded between States in written form and governed by international law…” In the US, the term “treaty” is often conflated with the process for entering a treaty as outlined in Article II of the Constitution, which states that “[The President] shall have Power, by and with the Advice and Consent of the Senate, to make Treaties, provided two thirds of the Senators present concur…” This does not define a treaty, but is one process for joining them. In practice, the US enters treaties all the time without going through the Article II process (take, for example, NAFTA or the 1945 Yalta Agreement).

These concepts take on a particularly unusual form in the context of the Korean War discussion, as the US participation in the conflict occurred under unique legal circumstances. The war began with the North’s invasion of South Korea, on June 25, 1950. That same day, the UN Security Council passed UNSCR 82 condemning the invasion. UNSCR 83 subsequently recommended that UN members “furnish such assistance to the Republic of Korea as may be necessary to repel the armed attack and to restore international peace and security in the area” and UNSCR 84 established the United Nations Command and requested it be led by the United States.

Together with President Truman’s Article II powers as Commander-in-Chief, these resolutions formed the legal basis for US intervention in the conflict, rather than a Congressional declaration of war, as provided for in Article I, Section 8, of the US Constitution. Congress neither made a declaration nor formally authorized the use of military force (Congress’s preferred method for authorizing war since World War II). In fact, at the time, Congress’s involvement was largely limited to coordinating funding appropriations for the war effort.

In short, there is no act of Congress which needs to be overridden to make peace. Given that UNSCRs 82 through 84 are still on the books a treaty and/or new set of UN Resolutions would still be necessary to change the state of engagement for other UN Command sending states and be viewed by North Korea as politically valuable. Because the US’s vote on the Security Council is controlled by the Executive Branch, this could allow for the process to be more or less kept within the Executive Branch and theoretically gives the President more latitude.

That is not to say that practically the President could or would not need Congressional approval to enter a peace treaty, especially depending on what is agreed to. Furthermore, even though there was no Congressional declaration of war, there is plenty precedent in US history for resolving undeclared wars with formal peace treaties too, such as the 1800 Treaty of Mortefontaine ending the French Quasi-War, or more recently the Paris Peace Accords ending US involvement in Vietnam. Congress likely has both the interest in checking the Executive Branch, and the power to do so. Below are a few options for Congressional involvement.

Peace Treaty with the advice and consent of the Senate

The most well-known option for the US would involve the President negotiating a treaty and sending it to the Senate for advice and consent. Assuming the Senate approved, the President would then have the authority to enter into a peace treaty with North Korea and formally end the Korean War (other countries, such as South Korea, would also presumably be involved in negotiations and would likely have to ratify the treaty in accordance with their own domestic laws). This tends to be the preferred method for international agreements deemed priorities to US national security, including many arms control agreements.

Though domestic politics sometimes results in the Executive preferring other pathways, the Senate has tools to dissuade the President from circumventing Congressional channels. In 2002, President Bush considered approving the Moscow Treaty as an executive agreement, before a strong bi-partisan outcry in the Senate led him to pursue an advice and consent approach.

Nevertheless, at present, given US domestic politics and continued Kim rule in Pyongyang, it’s hard to imagine a peace treaty with North Korea garnering support from two-thirds of the Senate.

Congressional-Executive Agreement

A Congressional-Executive Agreement, in contrast to the Senate-based approach, is a law voted on and passed by a simple majority in both houses of Congress and then signed by the President (thus becoming federal law), which gives the President authority to enter a treaty. Though it involves a lower voting threshold, this path isn’t exactly a cakewalk either.  

But here there are possible backdoors too. For instance, Congress doesn’t necessarily need to pass a new law authorizing the President to sign a peace treaty. The statutory authority can come from previous legislation. Any such law, or treaty, passed previously which could be interpreted to authorize the President to enter a treaty ending the Korean War could work. I am not sure if there is any existing statutory authority that could fit the bill for this situation, but welcome any thoughts from readers.

There are downsides with relying on pre-existing statutory authority to bypass Congress. Not only might Congress cry foul, but the President would also be limited to only allowing provisions into the treaty for which there is pre-existing statutory authority. Say one of the peace treaty provisions was the removal of certain sanctions the US had unilaterally imposed on North Korea. If those sanctions were passed by Congress, then they cannot be removed without Congress.

Executive Agreements and UN Resolutions

Under narrow circumstances, the Constitution allows the President to enter treaties by executive authority if the items agreed within the treaty fall under the President’s powers. For example, the President can negotiate and sign a Status of Forces Agreement with another state because of his authority as Commander-in-Chief. Given that President Truman used these same authorities to involve the US in the Korean War, it is conceivable that they could be used to justify an executive agreement formally ending the war. 

For this to be possible, and without additional delegated authority from Congress, the scope of the settlement would have to be relatively narrow and would therefore face some of the same challenges as relying on pre-existing statutory authority.

At the international level, because US involvement in the Korean War formally began with UNSCR 83 and 84, the US could (in concert with other members of the UNSC) also pass a resolution retracting earlier resolutions in whole or in part. As the US’s vote is controlled by the Executive, this approach would keep the entire legal mechanism behind a peace settlement within the executive branch.

Working towards peace

As the latter prospect indicates, there are some interesting additional avenues available when some of the above options are combined. For example, the President could issue a “peace declaration” ending the war and follow it with a UN Resolution, specifically pursuant to the UNSC’s Chapter VII authorities (which are a source of international law). Chapter VII of the UN Charter gives the body broad powers and resolutions passed under it have the force of treaty. As the US has previously ratified the UN charter, the legal authority to make and enter an international treaty ending the Korean War theoretically already exists within the UN. This option would have the interesting (albeit unfortunate) effect of binding the US under international law but not necessarily binding the US under domestic law. This is similar to how the Obama administration entered the Iran nuclear deal. As experiences with the Trump administration’s policy towards the deal highlight, there are limitations on the extent to which this path can bind the US at a domestic level. Coupling the UNSC mechanism with a Congressional-Executive Agreement or an Executive Agreement would be more binding and enduring under US domestic law, though not entirely free of political pitfalls.

In short, formally ending the Korean War would likely require some type of formal peace treaty and possibly a corresponding UN Security Council Resolution in addition. Though the latter is much easier politically, it would be difficult for the US to join the former without bringing Congress along and doing so would likely require significant concessions, verification mechanisms, and reassurance measures from North Korea. There are advantages and disadvantages to this. The domestic challenges involved in securing a more formal peace agreement could, with sufficient diplomatic coordination and skill, be a source of negotiating leverage with Pyongyang. On the other hand, these challenges could just as easily cut the other direction and paralyze talks.

Ultimately any path the US pursues will have to balance the above considerations.


  1. b. (History)

    I would much appreciate a similarly detailed elaboration on the processes by which the US President can attempt to exit a Senate-ratified treaty. The relevant cases here are ABM and INF.

    • Shea (History)

      You should look at Goldwater v Carter (1979). Basically, Carter decided to leave our treaty with Taiwan and Goldwater challenged it in court. https://en.wikipedia.org/wiki/Goldwater_v._Carter

      The Supreme Court ruled they weren’t the right place to answer this question on if we should still have a mutual defense treaty with Taiwan and sent Goldwater home. That said, they didn’t answer whether or not a President could unilaterally have the US exit a treaty. In that sense, the question is unresolved. In his concurring opinion, Justice Powell argued that in order to provoke a constitutional issue which the court could resolve, Congress would have to pass some resolution against the President’s move. So basically we probably won’t get an answer to something like that until the President leaves a treaty with such broad Congressional support that Congress acts to check the President.