The decision of Indian Prime Minister Narendra Modi and his Hindu nationalistic party, the Bharatiya Janata Party (BJP) to appoint hardline Hindu priest, Yogi Adityanath, as chief minister of Uttar Pradesh, India's most populous state where the party secured a jaw-dropping victory on March 11 stunned admirers and detractors alike.

While the response of his critics is more or less understandable, the reaction of supporters to the Yogi's appointment, especially middle-of-the-road liberals drawn to the party for the hope that Modi generated, is most striking.

Their dismay over the choice of chief minister stems from Adityanath being no benign Yogi. Instead, he is the undisputed mascot of rabid, vitriolic and abusive supporters of Hindu sectarianism.

For the major part of his two-decade-long political career, the new chief minister has been BJP's enfant terrible and often remained unrestrained, even when party leaders wished to sheath their swords.

Adityanath has violated party discipline in the past and established a separate vigilante group, Hindu Yuva Vahini. He put up candidates against the party in state elections in the past and in the recent elections.

Despite this, his appointment provides perhaps the best indication of the BJP's future political strategy.

Appointing a zealot

Within hours of the Yogi being named chief minister, news websites strung together collections of his most divisive statements. Targets of his hatred are diverse, from Nobel Peace Prize recipient and Apostle of Peace, Mother Teresa, to the King of Bollywood, Shahrukh Khan.

In October 2014, the Yogi spearheaded a campaign against Muslims claiming they had launched "love jihad" against Hindus by training Muslim youth to seduce Hindu girls.

He asserted on his website that the latest holy war was a "system where a girl surrounded with fragrance is enticed into a stinking world; where the girl leaves her civilised parents for parents who might have been siblings in the past; where purity is replaced with ugliness; where relationships have no meaning; where a woman is supposed to give birth every nine months; where the girl is not free to practise her religion; and if the girl realises her mistakes and wants to be freed, she is sold off."

Modi's liberal backers are disappointed because, in their assessment, the prime minister has wasted an opportunity to put the state's economic development on overdrive.

The fear is that Adityanath's appointment sends a signal to BJP cadre that the state government will prioritise Hindutva-centric promises in its election manifesto.

With Adityanath becoming chief minister of India's most politically influential state, the fringe has become more mainstream than ever before in Modi's India.

These include imposing legal ban on the practice of oral divorce among Muslims, forming "anti-Romeo" police squads to prevent Muslim youth from wooing Hindu girls, shutting down mechanised abattoirs and illegal slaughterhouses, and, of course, speeding up processes to remove hurdles to build a temple deifying Lord Rama in Ayodhya, epicentre of independent India's longest lasting political dispute and so on.

These measures will add to the disquiet of already anxious Indian Muslims who comprise more that 14.2 percent of the population according to census figures of 2011.

Fringe becomes mainstream

In the biography of Modi, which I wrote before he became prime minister, a chapter was titled - "Janus - The March Begins", denoting his two-faced personality.

During his tenure as Gujarat chief minister, and even thereafter, he has been at ease proclaiming India's development was his primary objective while promoting politics that sharpened social prejudice.

In comments after the Yogi was inaugurated in office, Modi referred to Uttar Pradesh as Uttam Pradesh, the Hindi for "finest state".

It has been Modi's tactical brilliance that he has kept both detractors and followers confused over which face to believe in: the "emperor of Hindu hearts" or the "development man"?

In 2014, his first statement after entering parliament was to term it "temple of democracy", a declaration that surprised most because he entered office with the image of a hardline Hindu nationalist and potentially authoritarian leader. Thereafter, he invited leaders from the South Asian Association for Regional Cooperation (SAARC) nations to his inauguration ceremony.

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Yet, within weeks in important by-elections in Uttar Pradesh, he nominated Adityanath as the party campaign's spearhead.

For several months, Modi looked the other way as cabinet colleagues used abusive language against adversaries, allied organisations organised controversial "reconversion" programme to bring Muslims "back into the Hindu fold" and when churches were desecrated.

Former US President Barack Obama, during his visit to India in January 2015, reminded the need to uphold religious freedom and constitutional rights. Modi followed on this by holding a meeting with Muslim and Christian religious leaders.

After the BJP's spectacular victory in Uttar Pradesh and other states, Modi's victory speech was markedly humble and he promised to be more socially inclusive and accommodative towards critics.

"Power is acquired by majority, governments are run by consensus," he had declared to widespread applause. A few commentators, including me, appreciated this and wondered if the weight of the mandate had sobered Modi. Adityanath's appointment belies such optimism.

Because of his dual-trait, it would be early to fear the demise of development-based governance in Uttar Pradesh. Critics, however, will conclude that a polarised India, where Muslims lead quasi-ghettoised lives, constantly under social suspicion and state watch is the "New India" that Modi promised.

Modi can yet again turn his government's wheels towards developmental programmes, using the Yogi as a shield to ward off fringe forces.

The trouble, however, is that with Adityanath becoming chief minister of India's most politically influential state, the fringe has become more mainstream than ever before in Modi's India.

Nilanjan Mukhopadhyay is a Delhi-based writer and journalist with a special interest in Hindu nationalistic politics. He is the author of Narendra Modi: The Man, The Times.

The views expressed in this article are the author's own and do not necessarily reflect Al Jazeera's editorial policy.