NEW DELHI — After several decades of mutual suspicion, India and the United States have been inching toward better diplomatic, military, and economic relations with one another. Even so, troubling issues still cloud the horizon.

The commanding officer of U.S. forces in Asia and the Pacific, Adm. Timothy J. Keating, was here 10 days ago to nudge that process along. "There has been a sea change in relations between India and the United States," the admiral said, noting that the last time he had been in India was in 1985 when he was the flag lieutenant for a predecessor, Adm. William Crowe.

"We are natural partners," Keating said, "even though we may not see things eye to eye in every instance."

This week, U.S. aircraft carriers Nimitz and Kitty Hawk and 11 other warships are scheduled to join the Indian aircraft carrier Viraat and six more warships, two Japanese destroyers, a frigate and an oiler from Australia, and a frigate from Singapore in a six-day wargame called Malabar 07 in the Indian Ocean. That will be the most powerful U.S. flotilla to train with the Indians.

Further, India has invited two American aircraft makers, Lockheed Martin and Boeing, to bid on a $10 billion contract to build 126 jet fighter-bombers, which would be the largest U.S. arms sale to India ever. Bids from one manufacturer each in Russia, France, Sweden, and a European consortium have also been requested by year-end.

Trade between India and the U.S. came to $18 billion worth in the first half of 2007, up 20 percent from the same period last year. The U.S. has become the largest foreign investor in India, with a total inflow of $6.6 billion by 2006. That is far less, however, than U.S. trade with and investment in China or Japan.

Lastly, the most visible symbol of improved Indian-American relations is the civil nuclear agreement proposed by President George W. Bush and accepted by Prime Minister Manmohan Singh here in July 2005. It provides for U.S. assistance to India for peaceful uses of nuclear energy but bans transfer of that assistance to India's nuclear weapons program.

The rift between India and America began shortly after India gained independence from Britain in 1947. India was shaped, says Teresita Schaffer, an American diplomat with long experience in India, "by its anti-colonial history, non-alignment between the world's two major blocs, (and) the related moral voice India wanted to inject into world affairs."

In those early days of the Cold War between the U.S. and the Soviet Union, however, Secretary of State John Foster Dulles of the Eisenhower administration asserted that India's neutrality was "an immoral and shortsighted conception." Moreover, India bought most of its weapons from the Soviet Union, making New Delhi seem pro-Soviet, and tested nuclear weapons in 1974 and 1998.

The end of the Cold War, the shedding of economic socialism in New Delhi, and the rise of China as a potential rival caused India to rethink its relations with the U.S. India, Schaffer says, began to see the U.S. "as the key external friend who could help it realize its global ambitions." In turn, Washington came to "accept that it was going to have to deal with India as a nuclear power."

The nuclear agreement, despite having passed initial tests in the U.S. Congress, 359-68 in the House and 85-12 in the Senate, is still highly controversial. Some Congressmen have expressed concern that India would not keep separate its civilian and military nuclear developments. Indian leftist have vigorously asserted that the agreement infringes on Indian sovereignty.

Similarly, critics of India's relations with the U.S. said they would demonstrate against U.S. warships in the Malabar exercise. Although officials of the participating nations asserted that Malabar was not aimed at China, an Indian defense specialist, Lawrence Prabhakar, said in the Asia Times it sent a message to the Chinese navy that "its future presence will not go unchallenged in the Indian Ocean."

A minor indicator of India's reluctance to be too closely associated with the U.S. was the cool, almost stealthy reception of Adm. Keating. While he met with India's foreign and defense ministers and the top military leaders, the press was kept at arm's length. No briefings were arranged, Keating's address to a think tank was off the record, and a meeting with reporters late in the day was limited.

Even coverage of the admiral's wreath laying at India Gate, India's memorial to the nation's war dead, drew no television cameras.

Richard Halloran is a Honolulu-based journalist and former New York Times correspondent in Asia. His column appears weekly in Sunday's Focus section.