Pompeo travelled to Sri Lanka and the Maldives, where China has sought strategic inroads, immediately after talks in Delhi
Two days of meetings by the top US and Indian diplomatic and defence chiefs in New Delhi underscored a desire for growing military cooperation, driven by mutual distrust of China.
Deadly clashes between Indian and Chinese troops over a disputed border region have given the Pentagon fresh fuel to draw Delhi closer, as it seeks a coalition to counter what the US sees as the rapid expansion of China's military presence across the Indo-Pacific region.
In two days of talks on Monday and Tuesday, couched as the third annual 2+2 discussions, US Secretary of State Mike Pompeo and Secretary of Defence Mark Esper agreed to share with India geospatial satellite and sensor intelligence.
They laid the groundwork for more military exchanges and cooperation on cybersecurity and space, as well as increasing arms sales, the US particularly pressing India to buy US F-18 fighter jets for its navy.
And both sides cheered the addition of Australia to the upcoming Malabar exercises in the Indian Ocean, joining the US, Indian and Japanese navies, an informal relationship now dubbed "The Quad."
"I think the tide has turned," Pompeo told Indian newspaper The Print.
"I think the world has begun to recognize the threat posed by the ideology that emanates from the Chinese Communist Party. And so yes, I think my Indian counterparts get that."
The US is anxious to build partnerships to hem in China's expansion, and India is a key focus.
The Delhi talks took place just days after Washington piqued China with the announcement of the sale of several billion dollars' worth of advanced military systems to Taiwan.
And immediately following the talks, Pompeo travelled to Sri Lanka and the Maldives, where China has sought strategic inroads.
The deadly confrontation between Chinese and Indian troops in a remote, disputed part of their long border earlier this year then played into US hands as it seeks to rally a global anti-Beijing movement.
India has requested US support, from endorsing its position diplomatically to supplying satellite intelligence and special cold weather gear.
In New Delhi, the US eagerness was palpable.
"This may be the most, certainly one of the most, consequential relationships for the United States in this century," Esper told reporters.
Amid the talks, Pompeo and Esper set time to visit India's National War Memorial.
In a well-choreographed ritual, they laid wreaths of white flowers and stood silent for a good two minutes. No other senior US official had ever done so.
And Esper, with his wife, managed to tour three New Delhi cultural sites, including a museum to Gandhi and the Red Fort, to underline their interest in the country.
No longer non-aligned?
Officially India hews to a policy of "strategic autonomy," Modi's updated iteration of its famous principle of non-alignment.
But in reality, Beijing's challenge has pushed New Delhi off the fence.
"The border spat in Ladakh has woken New Delhi up to the reality of the China threat," said Michael Kugelman of the Wilson Center in Washington.
"The US and India are now on the same page when it comes to China threat perceptions."
Harsh V Pant, head of strategic studies at the New Delhi-based Observer Research Foundation, said India is now in the "same league" as countries around the South China Sea, facing Chinese claims to sovereignty that overlap theirs.
"India has discarded non-alignment long ago but loves the rhetoric of non-alignment," Pant said.
Still there are limits. The refusal of counterparts Minister of Defence Rajnath Singh and Minister of External Affairs S Jaishankar to mention China in statements at the end of the 2+2 summit raised a question of whether they are really on board.
Pant says that's understood, however, and US officials agreed.
"It is a very critical time and everyone is trying to figure out best responses to the situation," Pant said. "And since we are also holding talks with them –- we have to be very sensitive about what we say and what we don't."
Washington remains patient, likewise hoping to sink a hook with the sale of F-18s, which would enhance the potential for inter-operability.
Yet no one is talking about a formal alliance that would include, as the United States does in more committed partnerships, joint military patrols.
"Washington views its top defence partners as allies that are willing to partner operationally," Kugelman told AFP.
"New Delhi, however, continues to insist on the principle of strategic autonomy, which rules out its participation in military alliances."