President Barack Obama handed Narendra Modi a personal triumph by accepting the Indian prime minister's invitation to attend India's Republic Day celebrations on Monday, January 26. The holiday commemorates India adopting its constitution, and affirms the nation's commitment to religious liberties. And it's that latter nature of the holiday that makes it critical for President Obama to ensure that Modi and his Hindu triumphalist cronies don't see the commander-in-chief's visit as a clean chit for their recent attacks on religious liberties.

Obama's visit isn't just about India's Republic Day, of course. It's part of the president's broader Asia initiative to get India, like China, to cut carbon emissions, while strengthening America and India's trade and security ties as a counterweight to China's growing influence. But fighting global warming in exchange for tolerating religious persecution is hardly a good trade off.

Modi is new in office, and has yet to prove he's a worthy partner. He won a great victory in parliamentary elections by focusing, laser-like, on economic and governance issues — and downplaying his Hindu nationalism. But when he was chief minister of Gujarat, India experienced one of its worst post-independence incidents of anti-Muslim bloodletting by Hindu fundamentalists, some of them aligned with Modi's Bharatiya Janata Party, provoking the U.S. to impose a visa ban on him.

Modi refused to apologize for the violence during his recent campaign, dismissing pleas to do so as a ploy to distract from his message of "development and jobs." But now that Hindu nationalists — some in his own cabinet — are distracting from this economic message, Modi seems blissfully unperturbed.

His education minister replaced German with Sanskrit as the third language option in schools for government employee children in the middle of the school year, creating a huge furor. Why did she do this? Because it's the language of Hindu scriptures — never mind that it has little practical relevance in modernizing India, where parents overwhelmingly prefer other languages. Nor is this an isolated attempt at scriptural chauvinism by Modi officials. India's minister of science and technology has asserted — in a national science conference inaugurated by Modi no less! — that ancient Indians, not Greeks, discovered the Pythagorean theorem. At the same conference, a respected pilot asserted not only that Hindus invented planes thousands of years before the Wright brothers, but that these planes could fly in any direction — and between planets to boot! Such claims are in keeping with Modi's own boast, previously confined to fringe gurus, that Indians knew genetics and plastic surgery thousands of years ago — otherwise how could Hindu god Ganesh have acquired an elephant head?

All of this jingoism would be comical if it weren't accompanied with chilling calls by militant Hindu supremacist outfits such as the Rashtriya Swayamsevak Sangh, where Modi cut his political teeth, for upping India's Hindu presence from 80 percent to "100 percent by 2021."

This is no idle pronouncement. In September, the RSS partnered with a state BJP chapter to reignite its campaign against "love jihad" — or the alleged Islamist conspiracy to convert Hindu women by seducing or bribing them to marry Muslim men. But instead of chastising this naked attempt to incite anti-Muslim hatred, Modi's chairperson to the National Commission for Women justified it by noting that it represented understandable "outrage" against inter-faith marriages that are "against the norm."

This effort, moreover, was simply the opening act of a more ominous campaign to hold mass "reconversions" of Muslims and Christians to Hinduism in public ceremonies called ghar wapasis — or homecomings. Dubbing this a "reconversion" effort is a clever ploy that serves a dual purpose. First, it emphasizes RSS's incendiary claim that Islamic rulers and Christian missionaries illicitly converted Hindus who are now merely being returned to their true heritage. And second, it sets the stage to exempt the organization from the national ban on religious conversions it is seeking, effectively handing it a monopoly on the conversion business.

The ghar wapasi campaign provoked a major row in parliament. Opposition leaders demanded that Modi pledge to end the initiative. He resolutely resisted, even though this prevented legislation on his key economic reforms from moving forward. Moreover, he rechristened Christmas as Good Governance Day, cancelling this Christian national holiday for government employees while leaving the many Hindu holidays intact.

A delegation of Christians led by Rev. Dominic Emmanuel, a Roman Catholic priest, paid Modi a customary visit on Christmas and complained that ghar wapasis and other attacks were making them "feel insecure and fearful." They asked Modi to say a few public words condemning such activity to put their minds at ease. Modi coldly informed them, they report, that it wasn't his role to weigh in on every issue and they shouldn't fall for "media exaggerations."

A group of Indian Catholic Bishops has since issued a statement demanding that Modi intervene to stop such unconstitutional activities.

Modi will use Obama's visit as the West's vote of confidence in himself, and pooh-pooh growing domestic alarm over his creeping Hindutva agenda. It's probably too late for Obama to fall sick and take a rain check until the Modi government offers sure signs that it plans to protect religious rights. But the president should take this opportunity to unambiguously communicate that he is very troubled by the developments on Modi's watch thus far.

To that end, Obama should privately — but forcefully — express directly to Modi his dismay about attacks on India's religious minorities, and make sure that Modi understands that America's continued backing for India's Security Council bid depends on credible efforts to protect these minorities. He should pointedly emphasize in his public comments that what binds the two democracies are not just commercial ties but mutual traditions of tolerance. Above all, he should meet with Christian and Muslim leaders whom Modi has dissed in an open show of solidarity with them.

Modi held his own victory rally in Madison Square Garden during his September visit to the United States — unprecedented for a foreign leader. So if Obama takes some time off from official business to meet private citizens whose issues he cares about, he would hardly be acting out of line.

Obama can't ignore the political forces he'll be aiding and abetting in India.

India is a young democracy whose commitment to religious liberty is still fragile. On its Republic Day, President Obama should do nothing to undermine it.