For years, the Pakistani gambit has been what the veteran American international relations expert Stephen Cohen once described as negotiating with a gun to its own head.

The red line was simple – Pakistan does not have the ability to take on Indian air power. In any conventional military battle, it would lose, as it has in every war that it has fought with India.

Therefore, the warning from the Pakistani side was always – the moment you cross the border, we will go nuclear. One Pakistani general is said to have told a former Indian foreign minister – we know you can take Lahore, so why should we wait?

The fear of a nuclear retaliation had paralysed India’s options for many years. But what has happened with the Balakot air strikes is that a crucial red line has been crossed.

This line was the fear of what Pakistan might do if Indian forces cross the border. The thing is, actual nuclear war where two countries have used nuclear weapons on one another has never happened, so one really doesn’t know what might happen in such a conflict. The entire body of scholarship on this, in a sense, rests on expectation and assumption – the whole strategy is based on what you can make your opponent believe.

Till now, India believed, or Pakistan believed that India believed, that if the line was crossed, Pakistan would jump to using nuclear weapons. This is no longer true, and we are in a new era.

How has this been made possible? Through a straightforward calculation. India is committed to a ‘no-first-use’ nuclear doctrine, which means it will only use nuclear arsenal once attacked by such weapons. Pakistan has no such commitment for it believes its nuclear weapons give it the parity that it cannot hope to match in conventional weapons.

So how can India ensure that no matter how much a Pakistani first strike impairs its arsenal, it will always have second strike capability? It couldn’t, definitively, until the arrival late in 2018 of its first nuclear powered submarine, the INS Arihant. India is only the sixth country in the world to achieve a ‘triad’ or capacity to launch nuclear attacks from land, air and sea. That Arihant is indigenously built is an added advantage.

Now there are some questions about what state of preparedness India keeps this capability, but that the capability exists is not in doubt. The state of preparedness is a key question in nuclear strategy because any delay in action in a critical moment due to confusion in command and control structure would be fatal. Also, the enemy works out its own response based on assumptions of preparedness.

An earlier Indian quest, though never formally verified, of keeping its weapons in a heightened state of readiness through a manoeuvre known as the Cold Start Doctrine was countered (the Pakistanis believe, neutralised) by Pakistan’s development of tactical or limited range nuclear weapons which can be more swiftly deployed.

But the Arihant, at least for now, is a game-changer. No matter how intense the Pakistani first strike, and no matter how much damage it causes to Indian installations, Arihant would survive, and decimate Pakistani capabilities.

This guaranteed second strike capability is important for India because it is well understood in the India-Pakistan nuclear paradigm that a Pakistani first strike could be debilitating for India, probably destroying vast tracts of its northern regions but a retaliatory strike by India has the potential to destroy the nation of Pakistan.

It is, in a sense, though no one will say this openly, the confidence of this second-strike capability which India has tested in the Balakot air attack. It is designed to signal to the Pakistanis that the old red line has been obliterated. This is why Pakistan’s most significant reaction to the air strike has been to call a meeting of its National Command Authority which maintains its nukes.

India has told Pakistan that it is confident of its second-strike capability enough to erase the old red line – and Pakistan does not, yet, have credible capability to respond to this. As I wrote a few weeks ago, not enough attention is paid to India-Pakistan conflict in the oceans as it is on land and air. The time has come to pay that attention. A new age is upon us in South Asia.

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