The brutal killing of 20 personnel of the Indian Army, including a colonel-level officer, by China’s People’s Liberation Army (PLA) in the Galwan Valley on the night of June 15 will reverberate across India for a long time to come. Indian security personnel — from the armed forces, paramilitary forces, and the police — have often given their lives in the quest to defend India’s territorial integrity, sovereignty and the Constitution. And as often, their contribution is forgotten.

But Colonel Santosh Babu and the 19 other men killed in the line of duty will stay on in public memory for three reasons. First, this was the first time since 1975 that Indian blood was shed defending the border against China. Two, the nature of the killing was brutal — PLA, in what India has called a “pre-meditated” attack, violated norms of war. And India and China are not even officially at war. And finally, their killing has highlighted the place of Ladakh in general, and Galwan Valley in particular, as essential to India’s territorial imagination.

This, then, can make June 15 — or Ladakh 2020 — the moment when, for two generations of Indians, the security threat from China has become tangible and real. It can make it the moment when discussions about the “competitive-cooperative” relationship with China and how to navigate great power politics will move beyond the rarefied seminar circuits of elite analysts and assume a strong place in public consciousness. And it can make it the moment when China becomes an issue in Indian domestic politics, strongly tied to public opinion, partisan positions, and the idea of nationalism.

The intersection of domestic politics and foreign policy is old. Indeed, a lot of scholarship suggests that foreign policy itself is the extension of domestic politics and is shaped substantially by it.

In India’s case too, this has been true. But barring the 1962 war, and the criticism that the then Prime Minister Jawaharlal Nehru faced, the most critical foreign policy issue has been Pakistan. This is not surprising. The tragedy of Partition, Pakistan’s support for Khalistan, the Kashmir question, its sponsorship of terrorism in India which has cost thousands of lives, four wars (1948, 1965, 1971 and 1999), and the manner in which the external enemy (Pakistan) is often used in political discourse to demonise an internal constituency (Indian Muslims) lends the India-Pakistan relationship particular political salience. Indeed, as the saying in South Block goes, the real joint secretary in charge of the Pakistan desk at the ministry of external affairs is the Prime Minister of India. And that is because each decision on Pakistan is a political, not a bureaucratic, one.

The Indian strategic community has long recognised China as a threat. The border dispute and Beijing’s efforts to change the facts on the ground by its consistent incursions; its claim over Arunachal Pradesh, particularly Tawang; the large trade deficit; China’s firm support to its “all-weather friend”, Pakistan, now buttressed by the China-Pakistan economic corridor; its efforts to box in India by encouraging regimes hostile to New Delhi in the neighbourhood; its moves to thwart India’s legitimate ambitions (such as permanent membership of the Security Council or entry into the Nuclear Suppliers Group); and its ambitions to establish new style imperialism through the Belt and Road Initiative have all been closely noted and are a part of the institutional memory of the government of India.

But along with this, there is also a recognition of the power asymmetry between the two countries. India’s economy is much weaker; its military and technological capabilities don’t match up to China; its State capacity is more limited; and in the maze that is international politics, China is a more significant player and India cannot rely on partnerships and external bandwagoning. Along with it, India — at this stage of its economic development — needs foreign capital and investment, and deepening economic interdependence with China has been seen as a way to both neutralise the competitive elements and aid Indian development.

This measured policy approach worked because China was not an issue that animated public opinion. But it will now face a challenge. This is both because of China’s aggression (not unique to India — just ask Vietnam, Japan, Australia and others in its neighbourhood) and because in Indian democracy, policies cannot be completely out of sync with popular sentiment.

The killings of June 15 have suddenly woken a large number of citizens to the fact that Pakistan is an important, but perhaps not the most important, security challenge India confronts. The Chinese willingness to assert itself abroad under President Xi Jinping, and the power differential with India, makes it a more serious adversary. The calls for boycotting Chinese goods may be populist and rooted in ignorance of economic realities but they reflect the emerging mood about China, which is going beyond suspicion to a degree of loathing.

The evolution of public opinion is bound to have an impact on political discourse. And that is why even a prime minister such as Narendra Modi — who has proudly worn the badge of nationalism and presented himself as a security hawk — had to face tough questions, not just from critics but also more independent observers, about his claim on Friday night that there is no external presence in Indian territory. The Prime Minister’s Office, on Saturday, came up with a clarification. But the response to his initial statement is instructive. Indian public opinion is not in the mood to tolerate even the hint of a territorial concession to China anymore.

This, then, will have an impact on the politics of nationalism in India. The Bharatiya Janata Party (BJP) — by disengaging with Pakistan till it acts on terror and through the surgical and air strikes under its term in office — has projected itself as a staunchly nationalist force. But now, it will have to be accountable for its actions on China too. The well-meaning advice to the Opposition not to “politicise” the national security issue may go unheeded, for if the ruling dispensation has benefited from weaponising national security for electoral ends, the Opposition will seek to emulate the same. Expect the BJP to talk about Pakistan, and expect the Opposition to counter it with China from now on. Ladakh 2020 has introduced the China factor into Indian politics. Its consequences will be long-lasting.