As thousands of balloons filled with rubbish floated into South Korea in May and June, the world’s attention refocused on the simmering tensions in the Korean Peninsula. Relations between North and South Korea have never been described as ‘positive,’ but the last five years have been marked by a measure of stabilisation since the two countries signed the 2018 Inter-Korean Military Pact, with a reduction in military movements, surveillance and reconnaissance missions on both sides. In recent months, however, the situation has deteriorated, and these balloons are just the latest in a series of military and diplomatic escalations between the two long-time foes. In September 2023, for example, South Korea’s Constitutional Court repealed its ban on propaganda broadcasts into North Korea; and activists – often consisting of North Korean defectors and religious conservatives – have since conducted an information campaign against the North, blasting popular music across the border and launching balloons filled with propaganda leaflets, medicines and other cultural items, looking to infiltrate North Korea’s censorship of foreign information. In response, North Korea resumed regular missile testing and satellite launches, culminating in both sides withdrawing from the military pact in November 2023; and in January 2024, North Korea removed reunification of the Korean Peninsula as even a distant possibility, declaring South Korea an enemy state.

Psychological warfare and border-zone tensions

Although striking in nature, the impact of psychological warfare tactics – from aggressive rhetoric to garbage-filled balloons and K-pop broadcasts – has had a limited impact on each side’s respective populations. South Korea’s propaganda campaign is unlikely to mobilise the North’s public against its supreme leader, Kim Jong Un, while North Korea’s balloon campaign has gone largely unnoticed by residents of the South, barring the nuisance effect of sporadic flight delays through Seoul, and having to report balloons to local police. However, close to the Korean Demilitarised Zone (DMZ) – a 4-kilometre-wide buffer zone that functions as the border between the two – the situation is more dangerous, with increasing weaponisation and small-scale military encounters that have the potential to spiral into a serious confrontation. In January 2024, North Korea fired thousands of artillery shells into the DMZ, ostensibly for testing purposes, while building anti-tank barriers, reinforcing roads and planting landmines in the supposedly demilitarised zone. With expanding operations in the DMZ, South Korea intercepted three – allegedly accidental – incursions by North Korean soldiers into its territory in June, and local residents close to the DMZ have reported an increasing number of explosions, with one North Korean landmine detonating accidentally, killing or wounding an unspecified number of their soldiers that same month.

The push and pull of geopolitics

Given North and South Korea’s divergent military alliances and trade partnerships, the likelihood of an escalation in tensions will be additionally influenced by geopolitical factors. China, for instance, remains North Korea’s key partner in both economic and security matters, accounting for more than 90 percent of North Korea’s trade, and the two countries also share a mutual defence treaty which they renewed in 2021. In addition, North Korea has made notable efforts to expand relations with Russia, with Vladimir Putin’s visit to North Korea in June 2024 – his first in 24 years – resulting in enhanced economic and security cooperation between the two countries. Strengthened cooperation between North Korea, China and Russia have allowed North Korea to be less reliant on – and compliant towards – Western countries that continue to maintain sanctions on the authoritarian regime.

On the other side of the coin, trilateral security cooperation between South Korea, Japan and the US has also deepened. In June, the US participated in precision-guided weapons testing with South Korea – the first of its kind in seven years – and in July, the three countries agreed to strengthen security ties and institutionalise senior-level defence policy consultation, engagement and information sharing. Closer cooperation between South Korea, Japan and the US may well provide the intended deterrent effect against the growing threat of North Korea in the short to medium term, but it is also likely to exacerbate the arms race in the Korean Peninsula, with South Korea’s public already grappling with the question of whether the country should acquire nuclear weapons.

Posturing without preparedness

In recent months, Pyongyang has threatened to ‘thoroughly annihilate’ South Korea, while Seoul promised to respond in kind, specifically threatening to assassinate the North’s most prominent leaders. However, despite the proliferation in aggressive statements from leaders on both sides, and talk of nuclear armaments, the likelihood of a significant escalation in tensions culminating in military conflict is remote. Neither China nor Russia have expressed support for North Korea’s military intentions in South Korea. China’s primary objective is to ensure stability in the Korean Peninsula and prevent a largescale refugee crisis from spilling over its shared border with North Korea, while Russia remains engaged in its own military campaign in Ukraine, limiting its resources for conflict elsewhere. Without support from its allies, Pyongyang’s military options against its economically stronger neighbour are limited. Meanwhile, South Korea’s allies are similarly incentivised to reduce tensions and avert a conflict. The US is aware that North Korean missiles pose a threat to its west coast states, and Japan has long followed a policy of non-aggression in the region. South Korea will therefore continue to seek to avoid a confrontation, opting for deterrence tactics rather than direct military aggression.

With neither side really prepared for war, North and South Korea will continue to seek the delicate balance between responsiveness to aggression on the border, whilst steering clear of open conflict. This balance, however, is fraught with risk, given the removal of key diplomatic frameworks that sought to limit tensions in the region, and increasing weaponisation along the border zone, raising the potential for collisions that could evoke a disproportionate military response. Furthermore, the existence of nuclear weapons in North Korea’s arsenal makes the situation all the more dangerous, and such a response could quickly spiral out of control and involve state actors beyond the borders of North and South Korea.