US President Barack Obama has announced $10bn (£6.2bn) in new trade deals with India.
He was speaking in Mumbai at the start of a 10-day Asian tour designed to boost US exports and create jobs.
Obama also announced an easing of US export controls and rejected caricatures of India as a nation of "call centres."
Visiting the scene of the 2008 attacks in Mumbai, he said India and the US were united against terrorism.
"We will never forget," he said at a memorial to victims of the attack by Islamic militants.
The outdoor memorial is a fountain with floating flowers just off the lobby of the Taj Mahal Palace hotel, where he and his wife are staying as guests.
He described the hotel as a symbol of India's "strength and resilience". He also wrote in a memorial book: "The United States stands in solidarity with all of Mumbai and all of India in working to eradicate the scourge of terrorism."
More than 170 people died in a series of co-ordinated attacks across the city in November 2008.
Big contracts
The White House said the deals for new export business with India would help to support around 54,000 jobs in the United States.
Some of the deals expected to contribute to this included:
The sale by Boeing of 30 new 737 aircraft to private Indian airline SpiceJet. The White House says this will help support over 12,000 US jobs.
Preliminary agreement had been reached on the Indian purchase of 10 Boeing C-17s military transport planes.
The sale by GE of fighter 107 F414 jet engines to the Indian military.
A separate deal with GE worth $500m (£309m) for the sale of six heavy duty gas turbines and three steam turbines to India's Reliance Energy Ltd.
Harley-Davidson plans a new plant in India to assemble American-made motorcycle kits.
The White House said India had identified GE subsidiary GE Transportation, based in Erie, Pennsylvania, and Electro-Motive Diesel, of LaGrange, Illinois, a unit of Caterpillar Inc, as bidders to supply Indian railways with over 1,000 diesel locomotives over 10 years.
The president said the relationship between the US and India was one of the "defining and indispensable partnerships of the 21st Century.
"The sheer size and pace of India's progress in just two decades is one of the most stunning achievements in human history," he told an audience of US and Indian business leaders.
Mr Obama's tour follows US mid-term elections that saw heavy losses for Democrats, seen in part as punishment for the US administration's inability to tackle high unemployment.
Before the trip, Mr Obama spoke of the need for greater US access to India markets as part of a drive to double US exports over the next five years and help revive the economy at home.
Trade between India and the US was worth about $40bn in 2008 - still significantly less than US trade with other partners like China and Europe.
Mr Obama's plane, Air Force One, touched down in Mumbai at about midday (0700 GMT) after a 15-hour flight from Washington.
Security is tight for Mr Obama's visit. Thousands of Indian and US security personnel are deployed and a US naval warship is on patrol in the waters off the coast of the city.
The BBC's Sanjoy Majumder, in Mumbai, says that while residents are celebrating Diwali - the festival of light - celebrations in the city are muted because of the huge security operation.
Later on his trip, Mr Obama will announce a "comprehensive partnership" including economic ties in Indonesia, attend a G20 summit of global economic powers in Seoul and participate in an Asia-Pacific economic forum in Yokohama, Japan.
