Modi, a Hindu nationalist politician, is (until he becomes the prime minister) head of the government in the Indian state of Gujarat. He held that job in 2002 when fierce rioting between Hindus and Muslims broke out. In that capacity, it is alleged, he encouraged — or did nothing to stop — vigilante violence against Muslims and police complicit with the violence. More than one thousand people, most of them Muslims, died. Prosecutions of those accused in the killings have been minimal.

It is a dark episode in India’s history, and Modi comes out of it tainted. But his actual role in it remains unclear. Three Indian investigations have cleared him of specific culpability, although the probes have been criticized by human rights groups with credible concerns.

This is an important challenge for Indian democracy — one that many vocal groups in civil society are taking up — but the question for U.S. officials is: Does Modi’s behavior trump concerns of U.S. national interest? He is the only person ever to have been denied a visa on grounds of “severe violations of religious freedom,” which makes the decision look utterly arbitrary.

Consider, for example, the case of Nouri al-Maliki, prime minister of Iraq. He heads a government that is deeply sectarian and has been accused of involvement with death squads, reprisal killings and the systematic persecution of Sunnis in his country. And yet, far from being shunned, Maliki has been received in Washington as an honored guest on many occasions by two White House administrations.

Consider a report from the U.S. Commission on International Religious Freedom (USCIRF), the very body that singled out Modi. It lists countries that are of “particular concern” for their “systematic, ongoing and egregious” oppression of religious minorities. Saudi Arabia, whose leaders are paid enormous respect by Washington, is in that top tier. The report recommends that Pakistan be added to that list because of its persistent violence against minorities, which, the report says, is at an all-time high. The report also says that Iraq should be in this group. Not a single government official from any of these countries — or any other country anywhere — has ever been placed on a blacklist or been denied a visa for violating religious freedom. When human rights issues are used in a blatantly selective manner, they rightly invite charges of hypocrisy.

In this case, as often happens, U.S. foreign policy is guilty more of incoherence than conspiracy. When it was created in 1998, the USCIRF was eager to demonstrate that it was not going to focus exclusively on violence against Christians. The Gujarat riots took place soon afterward, and their brutality — and the seeming complicity of state authorities — attracted global attention. Hearings resulted in the blacklist and ban against Modi. No one at a high level in the Bush administration paid any attention because Modi was a regional official, unlikely — it was thought — to ever ascend to national office.

If the United States can shift policy on this matter, Modi will have to get over his irritation with America. More important, he will have to shift his country’s posture on a much larger series of issues. For several years, Indian foreign policy has been adrift, so much so that the country has almost disappeared as a serious player in the region and the world.

This is partly because India’s previous government ran out of steam, muddling along on every front, domestic and foreign. But it is also because New Delhi’s ruling elites remain ambivalent about the kind of foreign policy they should conduct, trapped between their old, Third World, anti-colonial impulses and the obvious requirements of a new Asia in which China is emerging as the dominant power. The result is that India has shied away from the kind of robust relationship with the United States that would help it economically, militarily and politically.

If the United States and India, the world’s oldest and largest democracies, could create a genuine partnership, it would be good for Asian stability, for global prosperity, and, most especially, for the cause of democracy and human rights around the world.

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