Mr Modi, who often faced questions over the killing of Muslims in the post-Godhra riots in 2002, did not refer to the controversial issue in his nearly an hour-long speech in Hindi.
"My definition of secularism is simple: 'India First'. Whatever you do, wherever you work, India should be the top priority for all its citizens," he said.
"Country is above all religions and ideologies," he argued and asked people to follow the same.
"I agree friends that as an Indian, as a citizen who loves India, you will also agree with my definition...We might do any work or take any decision, India should be supreme," he said.
"Nothing less than India's wellbeing should be our goal. And if this happens, secularism will automatically run in our blood," the Gujarat Chief Minister said.
Mr Modi was denied US visa on the issue of human rights violation.
Last week, the Wharton India Economic Forum cancelled Mr Modi's keynote address to the prestigious annual event because of opposition from a section of professors and students of the
University of Pennsylvania.
But, Mr Modi did not touch upon the controversial Wharton issue.
The event organised by the Overseas Friends of BJP was planned much in advance of the Wharton controversy.
Several hundred people gathered at two places - Edison in New Jersey and Chicago - to listen to Modi's speech.
In his address, Modi emphasised on skilled development of the youth - who now constitute 65 per cent of the total population of the country -- and asked the diaspora to help in holistic development of India - tourism being one of them.
During the speech, Mr Modi avoided being highly critical of the UPA Government at the Center but raised the issue of budget being allotted by the Center and by his own Gujarat Government for the skill development of the youth of the country.
"This shows the priorities of the two governments," he said.
"I am not using this platform to criticise any government, but want to keep before you some of the facts," he said.
Invoking Swami Vivekananda and youth in his speech, Mr Modi said "development" is the key to all the problems of the country.
Highlighting the development model of his government, because of which he has been re-elected time and again, Mr Modi said Gujarat today is a "ray of hope" in this "era of darkness" in the country.
Mr Modi also used the occasion to sell brand Gujarat and India as a tourism destination. He urged the large Indian diaspora to convince foreigners to visit India as tourists. Once they start coming to India, it will give a big boost to the country's tourism industry and strengthen the economy.
In particular, he urged, the hotel and motels association of the US - which is dominated by the Gujarati-origin people - to show India on the television sets of their rooms.
"This would be your big service to India. It is not always necessary to invest in India or send dollars, motivating people to travel to India is also another way of service," he said.
H R Shah, CEO of TV Asia claimed that his address was seen live by several million people across the globe.