Deen Dayal Upadhyaya asked three questions: were the people who framed the Constitution endowed with qualities of selflessness, an intense desire for public service and a deep knowledge of the rules of dharma as the rishis were? Or did they formulate this Smriti of a free India under the influence of the unsteady circumstances prevailing at the time? Did these people possess originality of thought or did they have a tendency to primarily imitate others?

Deen Dayal Upadhyaya’s implicit answers to these questions were in the negative: the Constitution-makers were not figures imbued with selflessness and dharma, they were overly under the thrall of the turbulent politics of that era, and their minds had been colonised by Western ideas. The founding fathers of the Republic of India were largely Anglophile Indians schooled in Western systems of thought; their work revealed no Indianness, no Bharatiyata.

The Constitution, therefore, was to him a flawed document, one incapable of guiding India towards the path of raj dharma. In fact, it condemned Hindus to slavery: “Self-rule and independence are considered to be synonyms. A deeper thinking will bring home to us the fact that even in a free country, the nation can remain in slavery.” The Hindu nation had been enslaved by inappropriate Westernisation.

The Constitution’s core conception of the nation, in his view, was fundamentally not Indian at all. The absence of the Hindu Rashtra idea in the Constitution was unacceptable for him, as it is to those who revere him. So what might they do about it?

The more conformist of the two BJP prime ministers India has had, the late Atal Bihari Vajpayee (in office from 1998 to 2004), took a moderate approach to constitutional change, arguing that “even in the mightiest fort one has to repair the parapet from time to time” (while VP Singh cautioned that the “tenants” should not go for “rebuilding in the name of repairs”). His rule saw no dramatic change in India’s constitutional arrangements, though his government did conduct a constitutional review that produced a 1,979-page report, largely unread.

There has so far been no dramatic challenge to the Constitution under the second BJP prime minister, Narendra Modi. Indeed, Deen Dayal Upadhyaya, who rejected the Constitution of India in conception, form and substance, would be astonished to find his supposed acolytes extolling its every line and holding special commemorations in Parliament with grandiloquent speeches to mark the anniversary not just of its adoption – which, after all, is Republic Day – but even of its passage by the constituent assembly in a newly anointed ‘Constitution Day’.

What would Deen Dayal Upadhyaya have made, I wonder, of a prime minister, who swears by him, saying that this Constitution – the very document that Deen Dayal Upadhyaya found fallacious, Westernised, un-Indian and devoid of chiti and virat shakti – is his “holy book”?

It is, of course, difficult to know whether we should take the Hindutvavadis’ claims to be admirers of the present secular, liberal, Western-influenced Constitution of India to be as sincere as their professions of devotion to Upadhyaya. Will Modi and his tribe, after consolidating their hold on both the Lok Sabha and the Rajya Sabha, and after taking over most of the state governments, feel emboldened to tear up the very Constitution to which they have so far so enthusiastically pledged allegiance?

There are already hints that the Constitution in its present form cannot long survive unscathed.

KN Govindacharya has declared that the Constitution must be transformed: “We are doing it very silently. Discussions and debates have been taking place for some time...There may be many gaps which need deliberations, and a cool, calm, dispassionate discussion needs the right atmosphere and a mechanism. However, this is just not possible in the media glare.”

Would a Hindutva-inspired revision of the Constitution, for example, move the issue of cow slaughter from the Directive Principles of the Constitution, where it is linked specifically to the preservation of milch cattle and scientific principles of animal husbandry, to somewhere more binding, and anchored more explicitly to religious sanction? Mr Govindacharya is clear: “The cow is part of our civilisational past and it reflects those values, it should be a civilisational continuity in the preamble. The cow, environment protection, all this requires constitutional protection. It is part of Hindu ethos, culture—like Bishnois who embrace death by hugging those trees, this is all ‘Bharatiya’ culture. Instead of assuming man is conqueror of nature, it is the duty of humans to protect nature, and all this must be incorporated in the Constitution.”

Environmentalists may well approve, but the key question remains whether a Hindutva-modified Constitution, assuming that it ever comes about, will retain the core principle of independent India, that all adult Indians are deemed equal, irrespective of religion. Or would it consciously embrace the central theme of Hindutva, which would discriminate against non-Hindus?

If it did so, it would be true to Hindutva as expounded by VD Savarkar, MS Golwalkar and Deen Dayal Upadhyaya, but not to the Hinduism of Swami Vivekananda or Mahatma Gandhi, who did not define citizenship or Indianness in terms of the gods one worshipped, what one ate, the way one dressed or where one went for pilgrimage. But if it did not do so, it would betray a century’s worth of political philosophising in the name of Hindutva, surrendering its tenets to the dominant nationalist stream it had long derided as “pseudo-secular”.

This will be a crucial dilemma for the Hindutva ideologues. Do they take the opportunity given to them by their crushing political majority – which might not endure if they wait too long – to remake the Constitution as their principal thinkers had advocated? Or do they accept that the reality of ruling a multi-ethnic, multi-lingual and multi-religious polity makes their goal of a Hindu Rashtra unattainable?

Another litmus test would lie in whether a revised Hindutva Constitution would mandate a Uniform Civil Code for all the citizens of India.

Leaders subscribing to Hindutva have long argued that differential laws based on religion – essentially the personal laws governing marriage, inheritance and divorce for Muslims, and also for other religious minorities – violate Article 44 of the Indian Constitution and have sowed the seeds of divisiveness between different communities; if we are all Hindus (albeit “Hindu Muhammadans”, “Hindu Christians” and so on) why should we not all be subject to one civil code?

Secular Congress leaders from Jawaharlal Nehru onwards have argued that while a Uniform Civil Code might be a desirable objective, it could only be adopted with the consent of the affected communities. This could not be obtained by pressure or by legal coercion; it required persuasion. Since minority leaders, especially Muslims, showed no inclination to be persuaded, seeing a uniform civil code as the imposition of majoritarian Hindu sensibilities, the idea needed to be deferred indefinitely, until the time was ripe.

Hindutva leaders have long mocked this approach as caving in to minority prejudices; accepting Islamic personal law, they argue, violates the human rights principles of gender equality by discriminating against Muslim women and allows unelected and in some cases self-appointed religious personalities to interpret religious dictates and so “lay down the law”. Could they now concede the permissibility of religious personal laws without losing credibility?

And would a Hindutva Constitution preserve the anomaly of Article 370, which grants a special status to the state of Jammu and Kashmir, to the extent that no law passed by the Parliament of India can apply to that state without being also passed by the constituent assembly of Jammu and Kashmir? Would the advocates of Hindutva allow the state to continue to restrict landholding to “state subjects”, a status a woman would lose, under Article 35A of the Constitution, if she married a man from outside the state?

India’s constitutionalists have long argued that it is a living document, susceptible to amendment in keeping with the evolving demands of time, subject of course to judicial interpretation, which has decreed that its “basic structure” cannot be tampered with.

Would transforming an egalitarian and secular Constitution into a document infused with the principles of Hindutva not violate its basic structure? And yet, can the advocates of Hindutva – the intellectual legatees of Veer Savarkar, MS Golwakar and Deen Dayal Upadhyaya – afford not to try?

One more Modi paradox here: the very Constitution he swears by is in the crosshairs of the most devoted of his followers. During the huge national outcry in mid-2018 over my public statement that, if re-elected, the Sanghivadis would turn India into a mirror image of the majoritarian state next door – a “Hindu Pakistan” – I challenged the prime minister and his acolytes to end the controversy by disavowing their avowed goal of a Hindu Rashtra. None did.

I put the proposition to a Modi government minister with whom I shared a stage at a media-organised conclave; he evaded the question. I tried on television as well: “Let the prime minister say,” I declared, “that he admires Deen Dayal Upadhyaya but disagrees with him on the Constitution.” The prime minister said no such thing. It is clear that whatever their lips enunciate about the Constitution, their heart remains with the Hindutva doctrine that is antithetical to it.

All of us who care about the spirit of Indian pluralism and religious freedom, which are enshrined in our Constitution, must resist attempts to change its fundamental character. For the Constitution as it currently exists is a reflection of India’s pluralist soul. To destroy that would be to dismember the very idea of India that animated our struggle for freedom. A Sanghivadi India would no longer be the India that Gandhi, Nehru, Dr Ambedkar and Maulana Azad fought to free. It would merely be a Hindutva imitation of Pakistan.