The incident that claimed the lives of 20 soldiers near the disputed border between India and China erupted over roadwork.

Territorial conflicts between the two countries date back to 1962, when Chinese troops crossed the border with India, invading territory in the Himalayas – on which Beijing had long been laying claims. The ensuing war was short, but the confrontation has been smouldering on since then: Chinese and Indian patrols keep crossing paths near the disputed territory, engaging in the occasional scuffle and the rare full-blown brawl with sticks and rocks.

On Monday June 15, a skirmish in the Ladakh region near the border got unusually violent, causing 20 casualties among Indian soldiers. The reason behind the escalation appears to be Chinese opposition to India’s road-building operations in the borderland.

Specifically, it is thought that China takes exception to India’s plans to complete the Darbuk–Shyok–DBO Road, which runs parallel to the disputed border, and whose main section was inaugurated in April 2019. The road is intended to connect Ladakh’s capital, Leh, with the Daulat Beg Oldi base, a military installation that features the world’s highest airstrip and is extremely close to Chinese territory.

“It's an all-weather road,” explains Aaditya Dave, a research analyst at the Royal United Services Institute (RUSI). “It allows troops to move on it even in cool weather. It also has feeder roads that stem off from the main road and move towards the Line of Actual Control.” That line, though, is more of a fuzzy demarcation between China and India. And that’s where the problem lies. “It is closer to the border, and closer to areas China seeks to claim,” says Dave.

Both sides have deployed troops in the region since the start of the confrontation almost six decades ago, but until recently there was a notable difference between the two players in terms of infrastructure. While China boasts a ramified network of roads near the border, India has only recently started to catch up. “There have been quite a few transgressions from China into India, in areas where India had limited troop access – essentially, where patrols move on foot,” Dave says. “The objective from the Indian side has been to try and narrow the gap.”

Interestingly, if such a gap was allowed to develop in the first place, it was partly because of a deliberate Indian strategy. According to Gareth Price, a senior research fellow at Chatham House, following the 1962 war India believed that the lack of decent routes near the fractious border might actually be a plus – a way to hamper a possible Chinese advance on Indian territory.

“The thinking was: ‘If we keep the infrastructure poor, it would delay a Chinese invasion’,” Price says. “In the 2000s, India suddenly thought: ‘Actually we might build infrastructure so we can get our troops to the border quicker, and move troops around’.”

The main trigger for that change of mindset, according to RUSI’s Dave, was that the gap with China had grown too yawning to be ignored.

“There was definitely a shift in perspective, and I think one of the key themes would have been the fact that there was such a large gap: the fact that Indian troops, to actually get to the border, had to walk in a very inhospitable terrain,” he says. “While Chinese groups can come up to their side of the Line of Actual Control using all sorts of vehicles, heavier or lighter.”

Hence road-building – including in the Himalayas – became a priority, and a national security matter. So much so that in 2014, the Border Roads Organisation, the governmental agency deputed to build roads in India’s borderlands, was put under the direct control of the Ministry of Defence.

The end point of that change is Monday’s deadly skirmish, the diplomatic standoff, and the increased military buildup in the region. But according to Price, roads could be just part of the story. China might have turned aggressive in order to make a wider geopolitical point, he says.

“There is a huge amount of speculations ranging from – for instance – [the fact that] the new head of the World Health Organisation is meant to be an Indian, and some people are taking this as a warning not to investigate China's handling of the pandemic,” Price explains. “Or it could be that China is sending a warning [to India] for getting too close to America.”

One thing is certain: this could only have happened in the warm season. “You can only have standoffs in the summer,” Price says. “You can't do this in winter, because – even if you built roads – they would become impassable because of the Himalayan snow."

Gian Volpicelli is WIRED's politics editor. He tweets from @Gmvolpi

This article was originally published by WIRED UK